I personally just picked up a pair of Polk surround speakers. They list for about $235 for the pair but you can get them for cheaper. They also do come in white.

You know, if you just want the surround experience, some cheap bookshelves from Radio Shack or a similiar place will work. It won't be the best blend you can get but if you set them up right, you will be amazed at how well they could work. My friend uses these tiny little speakers for surrounds and it actually works nicely with his system.