So I am looking for any recommendations for models to use for the slave army that Spartacus led against the Rome Republic. I know their slaves were from all conquered areas and so there probably isn't a definitive range to go with. I figured I would ask though anyways and see if anyone had any knowledge of Spartacus' army composition or if anyway to portray a slave army could be done.

 I don't think they would have their native dress (armor, weapons, shields) since they are slaves/gladiatores.  Therefore, it would be a mix of AGR03, 04, and 10 for the light foot or maybe even the bulk of the force with a mix of figures from AGR09, peltasts, or AIT01. For formed foot, a mix of AIT01 and ARR008.  Cavalry could be a mix of AIT03, ARR05, AMA05, and maybe AMO03 or AGE05.  The bottom line is that most of the forces would be unarmored or irregualry armored and generic in look.   

Hi Curbic, 

The Greek (AGR) line would be a good place to start, but I'd also take a look at the Dacians (ADA), Celts (ACE), Moors (AMO), and Spanish (ASP) lines. These are what I would (and plan to) use for generic ancients proxies in projects such as yours. 

Enjoy! 

Good advice so far.  Given their victories over Roman armies, I'd expect a lot of them to be wearing captured Roman gear.   The idea that all these slaves suddenly reverted to their native dress and equipment is fanciful to say the least.