Re: Anthropomorphic races
Just my two cents; If you're not going for very "deep" detail on the various animals, pick one stereotypical thing about the races (reflexes for cats, size for elephants, sneakiness for weasels or rats, etc) and build a Fantasy-style racial package around that.
For more detailed "races", I'd reccommend either the After the Bomb rpg or Ironclaw, as they may be easier to get ahold of than most others. Another easy-to-purchase suplement might be Big Ears, Small Mouse for BESM.