A good rule of thumb is that if you can't sit down in a chair, raise your feet off of the floor and pull the bow back easily, its too much WEIGHT for you. This not only will keep you from hurting yourself by pulling a muscle (damaged shoulders are a common theme among some archers), but will make those cold mornings sitting on stand much easier because cold stiff muscles do not always like to pull a heavy string and may make you miss that great wall hanger!
FIXED it for ya.
I think what Wabbit said will get you started. One thing about buying a bow, it HAS to feel good in your hand, during the draw cycle and during the shot. At full draw, you dont want to feel cramped or streched out. You want to be able to get a good solid ancher point or 2 maybe 3 if you can. Dont worry about missing 4 out of 10. the ablility to put the arrow where you want it comes with time and patience. Take your time and find one that you really like and that you feel good with. Keep in mind while you look that if the draw length is too long or too short, it wont feel right, but that doesnt mean that it is not the right bow for you.
Good luck and WELCOME to the FEVER.
"When a hunter is in a tree stand with high moral values and with the proper hunting ethics and richer for the experience, that hunter is 20 feet closer to God." -Fred Bear
2012 Martin Cougar FC, Fury XT cam
CE PileDriver arrow, 535 grains