I know of two,
Bit Buckets posted their's a little while ago.
Bit Buckets CAD Library
Spectrum has been making one for a few years and we upgraded it a lot this summer/fall with still a bit more work to do before the season.
Spectrum Library
Both of these include a lot of the same parts and sources, like Vex Pro, AndyMark,
Team 610's Part Library, McMaster-Carr,
Andrew Lawrence's gear library and various vendor websites.