At BlogSkins you can view "...designs from some of the best people around the blogging community, and instantly and easily download them to your own Blogger, Movable Type, or other-powered site."

Elated Page Kits has some really nice blog templates as well. There are over 40 free PageKits (web site templates) available here. You can download the entire PageKit, including HTML and graphics, in .zip format, and you can also download the PSD (Adobe Photoshop) files for a 'Kit, so that you can customise the menu options and images.