My favorite is Raxles. They're in Clearwater, FLA. They just sent me and a friend a custom set of axles that let us squeeze a 2.0L DOHC 4g63 in a 2100lb Mirage hatchback with Expo brakes/hubs. The car was $60, the engine was free, and the custom axles are the most expensive parts at $150 ea. They come with heavy-duty joints, and are packed with AMSOIL synthetic grease. Lifetime warranty. Got them to VA in 2 days from when we ordered them.

:shamelessplug: