The first time I used CSS3's @font-face property in a .NET environment, I realized fonts didn't load right because the mime types in IIS were either wrong or non-existent. So here's a quick reference for what file formats you're going to need for proper @font-face usage:
.eot (application/vnd.ms-fontobject)
.svg (image/svg+xml)
.ttf (font/ttf)
.woff (font/x-woff)
The default mime types for .eot and .ttf are different than the ones above, but I replace the defaults with these. I'm just a front end guy, so these work for me for local development. If these are wrong or you know of a better way to do this, let me know and I'll update my post.