First time modeler for Source games and I have some questions.

Hey guys I’m a first time modeler for Garry’s Mod and all Source related games and was curious if anyone has information how to import the model into the game it self and what file format it has to be in and if the Source SDK has the tools I should be looking at and which ones I should be working with to attempt some form assembling into the games themselves, would appreciate it if someone could point me into the proper direction and or a few links on some decent information. you should find info here for Blender or 3dsMax