http://www.westelm.com/products/gallery-frames-a472/ (3rd down on the page)
The 13x13 frames have a simple, classic look and work great with 8x8 prints. However, they will need a custom cut mat to fit an 8x8 print - instructions on how to do that are here.
These frames have a nice wide moulding and look great without a mat.
http://www.potterybarn.com/products/wood-gallery-single-opening-frames/ (top one on the page)
If you just want a small, simple frame without a mat, this frame (which says 4x4" on the Pottery Barn site) will fit an 8x8 print perfectly if you remove the mat.
These frames come with everything you need, including the mat. I haven't used these frames myself so I can't vouch for their quality but they look like an easy solution for framing 8x8" prints.