I want to make a 2D platform game, but I don't know where to find 3D models for the platforms. I have read the tutorial here but I don't want those platforms. Thanks.
Try:
www.turbosquid.com
http://unity3d.com/unity/features/asset-importing
Make your own than... Their is a list of software you can use...
Bender is free...
Also, Unity does come with the common models (You can make a cube, use the scale tool to make it more "Your style").
Hope that helps you on your way =).