I was going to suggest Archery Talk... If its his first year, I wouldn't spend a lot of money on a bow, until you know for sure he likes it.
Bows are like anything else, there a people that are loyal to the death for certain manufacturers.
I shoot a Mathews, my wife shoots a Mathews, and we got my twelve year old son a new Mathews for Christmas last year. I started him out with a used Browning to make sure he was interested enough, to warrant the expense of the Mathews.
Sounds like your son would be able to do 50-60 pounds easily. Start off at a lower poundage and work up. Most bows are adjustable 10-15 pounds, depending on the brand.. So if you buy a bow that has a maximum poundage of 60 pounds, it could be lowered to 45-50 pounds.
Mathews, Bowtech, Browning, Martin are all good bows. Martin are the least expensive, but there is absolutely nothing wrong with them.
Before you buy any bow, go to a reputable shop to have them check his draw length. Making sure the bow you get fits him properly, is very important.
Once you narrow it down, Archery Talk has a great classified section where you can pick up 1-2 year old bows very reasonably priced.
I've bought 4 bows on there in the past and have had no problems.