http://smartphonethemes.com/preview.asp?ID=1687

http://smartphonethemes.com/preview.asp?ID=1688

http://smartphonethemes.com/preview.asp?ID=1686

Just copy the xml and the image file to your \Windows directory. The theme should then show up under 

   Settings->Home Screen.

Its quite easy to create your own theme ... and you can create things that look so much better than PPC themes. The current wysiwg editor for SmartPhone themes does not let you create these kind of themes ... but it shouldn't be too hard to write one up.