Lot's of good bikes out there, probably best to visit some local bike shops to see what they've got and to get an idea of what fits your budget. There's no one perfect brand, it's a lot like asking what car you should buy, depends a lot on your budget and interests. The good news is that the bike industry is pretty competitive so within a given price class the overall build and component quality tends to be similar. IOW, decide to spend say $800 on a new road bike and you won't see tremendous variation from brand to brand though you might really like the way one looks or feels when you test ride it.
In terms of getting started you should figure out where you plan to do most of your riding, as in on roads and paved paths, off road on trails or maybe a combination as well as what kind of riding as in commuting, general fitness, maybe longer day tours or perhaps you have an interest in competing or doing fast group rides with a local club. Based on that you can narrow things down to a road bike or mountain bike or maybe a cyclocross bike which can be very versatile first bikes as they run fast with road tires or handle a lot of dirt and gravel riding with knobby tires mounted but aren't as expensive, heavy or slow as full bore mountain bikes designed for really technical off road riding.
Spend some time on Google Maps or Bikeley.com or MapMyRide.com to get an idea of preferred bike routes in your area, that might help you narrow down what kind of bike you should focus on. If there's a ton of good road riding or perhaps extensive forests with trail systems or maybe a long gravel rails to trails that you'd like to use for fitness riding it might help with your decision.
Always test ride a bike before purchasing and make sure the shop spends time fitting you to a well sized bike. If they won't let you test ride (ideally more than a spin around the parking lot) or they don't spend some time fitting you or have you try different sized bikes or seem intent on 'convincing' you that a bike that feels too big or too small is actually perfect then it's time to check out other shops.
Once you pick out a bike you'll also want at least the following:
- Helmet
- Patch kit and pump or CO2 inflation system
- Some cycling shorts
- Water bottle or two plus bottle cage(s) for the bike
Other useful accessories include:
- Dedicated stiff soled cycling shoes
- Clipless pedal and cleat system (many new riders hold off on this till they're more confident with basic riding and it's a good idea to practice clipping and unclipping in a very safe place like a big grassy field or empty parking lot before taking them on the road)
- Cycling gloves
- Cycling jersey's to make it easy to carry food on your rides
- Extra clothes if you want to ride very often
Start by visiting some shops to see what they have. Very good used bikes come up all the time on Craigslist or ebay but unless you really know what you want and what size and can do some basic bike maintenance that can be a risky route for a beginner.
And especially if road riding and or organized day tours or even racing appeals to you then ask around at the shops to learn about local bike clubs that are open to new riders. That will really speed up the learning curve.
Good luck,
-Dave
