Hello Dalia!

I am delighted to answer your questions! Note that all my answers are (here is the caveat) subjective in the sense that they are opinions & personal experiences, other readers will be welcome to correct me & redirect you

First order of business: Welcome to cycling!!! A sport I personally totally adore, under all its shades!

Now, for your questions, Ill answer by addressing the key points:

(1) Price, price, price
 as everyone knows, you can easily buy a bike for 99$ through to 10,000$ throughout tens of dozens of stores around Montréalso, What CAN you spend? What SHOULD you spend? important questions to answer. In the world of cycling, usually 99$ will buy (maybe) one pedal on a pro bike...now, do you need a pro bike? Well, some nearly-pro bikes are not too expensive and can be purchased for 2 to 3K$.
 Youll address the CAN part , Ill make some suggestions on the SHOULD
o 500$ or less: not worth considering given the info you provided
o Around 1000$: now we are starting to broach the realm of a bike that has some potential (for comfort, durability & relative performance)
o In my last 20 years of cycling (mountainbiking & road cycling), I have found that a sweet spot has been in the 2000$ price range, AFTER ALL is told (including shoes, helmet, bottle cages & bottles, clothing, gloves, basic tools, must have spare parts etc.). So, you could be looking at a 1300$-1500$ bike and when you tag on all the accessories, you easily creep up on the 2000$ price range.
o I have frequently spent well over that for myself, but the reality, is at around 2000$ all included, you are always getting a good bike with which you will evolve over the next 4-5 years?? let's imagine?
o My wife spent 1200$ on a Cannondale (just the bike), she rides road about 1000KM per year and she is very satisfied with it. I have a 3000$ Devinci (made in Quebec) which I have ridden about 30,000k in 6 years and feel I can ride for a long time again.
o The differences for the bike cost alone between the high prices will be in what is called the gruppo, the group of components attached to the frame (derailleurs, brakes, pedal system, hubs for your wheels etc.), and the higher the price, typically means the better quality gruppo youll get. Better quality typically means: lighter, stiffer and will keep its adjustments longer (between maintenance). You need not spend the money to have the Ferrari of grouppos, however, spending for the mid range of quality will serve you well over time.

(2) What type of frame for the bike: Aluminium? Carbon?? Titanium??
 That usually goes with the priceI love aluminium frames with carbon front forks, but thats me
 I find Titanium to be very stiff on the old bones! But this is very subjective, + Titanium is out of my price range.
 If I had the money, I would love to buy a carbon fibre frame

(3) Musts (In My Very Humble Opinion)
 I suggest that the CARBON FIBER FORK is a must living in Quebec )
 CLEATED PEDALS: there are dozens of types & brands. Purist cyclists (and me!) will favour the Look Arc or Time type of systems over Shimano SPD (again, for road bikes). However, for beginners, it will typically be easier to get acquainted with your feet being attached to your bike with Shimano SPD types of pedals. However, Look Arc or Time will certainly be more efficient over time. Negotiate to get the pedals included in the price if buying new. Either way, if you go bike you have to go cleats, do not go for straps, those are death traps in todays world. And without cleats, your feet will never be properly positioned.
 GOOD SHOES TO GO WITH THE CLEATED PEDALS: The right position, the comfort (for the 8 to 10 hours youll ride in them) are critical.
 GOOD WHEELS: Good wheels are costly (anywhere from 200 to 500$ per wheel and more), Mavic (Cosmic Elite or Ksyrium for example) are tremendous wheels. The lighter they are, the better, but go with your budget. Negotiate to get these included in the price if buying new. I have Mavic Cosmic Elite wheels (Mavic being one of the standards with regards to wheels) and in 30,000 KM they have required ZERO maintenance thus far! And I ride Quebec/Montréal roads all the time.
 GOOD TIRES to go with the good wheels: Light tires & light inner tubes will make you happy over many kilometres. Heavy tires & inner tubes suck energy out of you because rolling/spinning weight is HEAVY. But then again, go with your budget!
 AN ERGONOMIC SEAT: Yes, there are gender specific seats, and you know what, they make a heck of a difference after spending 8 hours in a row on it!! My wife & I invested the 80 to 100$ to get our own and cannot say enough good things about them!
 A very well ventilated & light helmet: Your noggin will love you for it. Giro makes excellent helmets at every price point for instance, but the brand is irrelevant. The comfort for your head with as many ventilation points as possible are the best.
 Since we do live in Winter wonderland, A BIKE TRAINER: this is a device to which you attach your bike (rear wheel) and a friction mechanism provides for tension against your wheel, allowing to ride your own bike in the house. Why is that better than using a Sears exercise bike? The exercise bike will have all the good things about YOUR bike wrong: meaning, seating position, pedals etc. For between 200-300$ you should be able to find a good entry level (magnetic friction) bike trainer in just about any bike store. Youll use this from now untilEaster? Or when the snow melts, and youll use it for the next 15-20 years every winter. Great investment.

(4) Where to buy
 I wish I knew THE BEST PLACE! Everyone has a couple of favourite LBS (local bike stores). Certainly in your neighbourhood is a great place to start, encouraging local business etc. HOWEVER, it certainly helps to have: variety, expertise & volume (ensuring good prices & competitivity). But, most important about the LBS to choose is that you WILL NEED AFTER SALE service. Many stores now guarantee that if you buy from them they will service you first (before others) and ensure rapid service. The reality is that after a couple of rides on a new bike, you may need to bring it back in for fine tuning adjustments as cables settle in to the derailleur & brake housings, plus the component that attaches the handlebars to the bike (the neck) may be too long, too short, wrong angle etc. and you will need to change it. This type of post purchase fitting should be free of additional charges if the store is reputable.
 Over the years, I have frequented the following 4 places for various needs and have been very happy with quality-vs-price-vs-variety-vs-after-sale-service:
 a. Cycles ABC on Avenue du Parc (www.abccycles.com), Gary in the « upstairs road bikes » part of the store is a dedicated cyclist and offers great advice & service, and Francis in the parts department is a super wiz of parts. I like that store because they have good service, good prices, volume & variety. However, they get REALLY insanely busy, choose your time (avoid shopping rush hours and shop early in the season, or else you should totally avoid going)
 b. Primeau Velo in Laval (I live in NDG and it takes me 15 minutes to get there by Des Laurentides) (www.primeauvelo.com). Good variety, good technicians, excellent service.
 c. Cycles Gervais Rioux 514-278-1818: the owner & founder is a Canadian cycling champ (Gervais Rioux), his boutique is quite high-end, but even at 1500-2000$ you can get an amazing bike of his home brand (Argon 18). Their strength (in the store) will certainly be to fit you on the bike (adjusting seat, handlebar height plus length of the neck etc.) These guys are pros, however the shop is a boutique and prices can be scarybut, they are pros
 d. M.E.C.: quality clothing & quality parts at a great price.

If you are buying for long term, used may not necessarily help you along, but this is sooooo subjective that I hate saying it! You may find great great deals on www.kijiji.ca or Craigs list, butthe fact that youll need to get fitted on the bike & need after sale service

Once we get into the season, and start riding outside, I will advise you on my outings which shall be SLOW to start out with, and if you are so inclined to join in, you will be very welcome! The objective is to do this ride, not to win by doing it fast, so, I am training for endurance.

Should you have more questions & you find my comment relevant for you, please ask again!

Frederick, the veteran-wanna-be-cyclist