Multivariate tests are alot easier than people think. Here’s a sweet way to look at it and some killer tools to use.
Use Google Website Optimizer if you want something free and it will work…. however, if you want to use some other tools, here are a few.
Offermatica I think they were bought out by Ominture.
Split Test Accelerator This one comes highly recommened from Kirt Christensen with Manage My PPC.