I'm not sure how active the thread still is, but you might want to take a look here:
(144070.1). It's a mentoring program for US coaches. They'll pair you up with an experienced player to help you learn the game. At first glance, this game may seem easy to learn, but believe you me, there's a lot more to it, and player management is a crucial part of it.
My suggestion to you is this: Definitely keep Bowie. With proper training, he could really turn into a beast. Since he's a big man, you're going to want to pick up some more young big men for him to train with. I would not look at any potential lower than superstar (maybe star, but that's definitely the lowest you should look at). Preferably 18, but no older than 19. Don't overpay for your youngsters. I'd say at least 3 youngsters, but ideally, if you can afford it, 6. Play them at PF/C. When your financial situation can afford it, buy some decent guys to play PG, SG, and SF. You don't need big salaries at this level. I won DV with no player over $10k.