I am going to start shooting my own short films in the very near future and I need some sort of a sound suite for post production. Every film is littered with sounds not present while shooting, such as footsteps, scene cut sounds (like that noise when a scene is about to cut in Lost) odds and ins (doors shutting are typically added in, slams, etc, all that kind of stuff, none of it is the stock noise). So I need a sound suite that has all of these sounds either for free, or something that I can buy.

Any suggestions?