If you are a beginner first thing to do is take an approved motorcycle riders safety course. Really. do it or don't get on a motorcycle. You'll get a feel for what you want and how a bike feels under you. Remember to keep it under you! You're going to get a lot of prejudiced advice from people who thing what they ride is the best ride bar none. what one person likes isn't necessarily what someone else likes and it also depends on what you want to do with the bike. Commute to work? Ride with a group? Sight see in the mountains and deserts? Now go take a Motorcycle Safety Course. A lot of colleges have them. If you can find one not sponsored by a dealer you won't have to put up with the sales hype.
Ditto what dblshot said.
TAKE THE SAFETY COURSE. There's a lot to get used to as a new rider (or even as a seasoned rider on a new bike) -- balancing, shifting, braking, etc. No matter what you use the motorcycle for -- commuting to work, riding with a group, riding alone -- don't buy more motorcycle than you can readily handle.
If you later find you've outgrown the first bike you bought, you can always sell it. That's much more preferable than getting into an accident with a bike that was too big/powerful in the first place.