You might to look at pre-rendered 3D, would probably be much cheaper than hand-drawn sprites.
Is this true? I'm looking to reduce my art budget.
However, after a 2-3 months of looking around and working with 2 artists on concept art, I tend to see much more traditional hand-drawn artists than pre-rendered 3D artists for hire (e.g. look on deviantart). There are, however, quite a bit of cheap stock pre-rendered 3D art around.
So far, my opinion is that creative use of limited traditionally hand-drawn art looks better than cheap pre-rendered 3D art. Of course, I could be wrong.