Camelbak is key. I am a firm believer in the camelbak. (I own 4 different ones) There is no better way to stay hydrated. I think it is one of the best accessories you can buy for a bike. I race mtb's and for long races, love that camelbak. (plus it provides a little back protection if you endo)
And find a local bike shop (LBS). Try to find one with a welcome vibe. Talk to the people that work there, the good ones employ bikers! If something doesn't feel right, they will be able to look at you on your bike and help you fix it.
If an LBS is unavailable, bicycling.com is a great site with really good info.
Most of all, just enjoy riding. When training and racing, I often start feeling burnt out with riding and don't want to get on my bike. When this starts happening, I just go out for a ride at one of my favorite trails, forget about the comp or stopwatch, and just remember the reason I started: I love being on the bike.
Good luck for those getting out on the bike, stick too it, and just enjoy being out there!