+1. But just to add a little. If you can, visit a lot of bike shops and test ride a lot of bikes. Once you have done that, concentrate on the bike that you felt best on that is within your price range.
Also set a little money aside for such things as a helmet, pedals and shoes, a hydration system, shorts, and possibly gloves.
Helmets come in two types, less expensive and more expensive. Unless you are the type of person who has to wear the best brand name, buy a less expensive helmet, even a $14.00 WalMart helmet will work here. All helmets sold in the US have to conform to the same exact safety standard. The only things that add onto the price of the helmet are the number of vents, size adjustments, appearance, but mostly the name that is on it.
Most new bikes sold come without pedals or with a cheap pair of resin body pedals installed. This is so that an experienced rider can add his own pedals or a set of pedals that will work with the cleats that he already has on his shoes. Since you probably don't have a favorite pedal or a pair of cycling shoes, you have a lot of leeway here. Have the guys at your LBS show you different pedals and how they work. Buy the ones that you like best and then get a pair of shoes that will accept the cleats that will come with the pedals. Pedals can cost over $200 if you get a realy good race pair, much less if you are just getting cruiser pedals. Shoes are probably going to run $60.00 to $150.0 or so.
Your hydration system can be water bottles or a water bladder that you wear in a back pack. Both work very well so it is pretty much your choice. Look to spend $5 - $10 per water bottle and up to $20.00 per water bottle cage. I have seen the water bladder system, known as Camelbacs, going anywhere from $35.00 tp $70.00.
Cycling shorts are a good investment for your posterior. They have padding where it is needed most and there are no seams in the crotch to prevent chafing. You can get the traditional tight shorts that show off all that you own or you can get baggy shorts which is the tight shorts with a baggy shell over them. You can also get bib shorts which are all teh rage now or regular. The nice thing about them is that most of them have zippered pockets so that you don't have to worry about losing your keys or whatever. Price ranges vary widely here, normally $40.00 and up.
Gloves are really nice to have if you have a crash as they protect your palms. I don't know if you have ever had scraped or cut palms, but if you have, then you would know the importance of gloves.
There are a lot of other things like flat kits, pumps, and other tools that you may want to carry with you, plus jerseys or even full team kit if you can afford them, but that will come later down the line.
