Tribex is primarily Tribulus Terrestris. Tribulus Terrestris has not been shown to increase endogenous androgen production (which would aid in muscle accretion and fat loss) in either males OR females (Saudan, Baume, Emery, Strahm & Saugy, 2008).
Testosterone boosters do not necessarily double as fat burners. If one is losing fat using one, then it is because they are potentially gaining more muscle mass, or their diet is targeted that way, or (if a male) because of the higher testosterone levels (if it is FREE Testosterone). Females won't necessarily gain muscle or lose fat any faster by increasing testosterone levels (I actually just finished writin an article on this very topic).
As for there being "anything like Tribex on the market for females"; females CAN use Tribex.
If you're looking for something that can aid in recomping (which is what gaining muscle and losing fat simultaneously is), then look into a GH/testosterone booster, such as IGF-2 (I gained muscle and lost fat on this product, and it keeps me relatively lean, which says something, considering I easily eat ~4000 cal/day)! GH is actually what determines the rate at which a female gains muscle or loses fat (Kraemer & Ratamess, 2005); and although there is no evidence to prove that increasing testosterone in females does anything re results, there is no harm in trying to create the most anabolic environment possible.
However, really, most of it is in your DIET (I cannot stress that enough)!!!