comp.sys.sinclair Newsgroup
The birthplace of the Crap Game Competition.

World of Spectrum
Arguably the biggest ZX Spectrum fan site on the planet

Unsatisfactory Software's Crap Game Finder
An on-line searchable database of some of the worst, badly programmed and poorly executed excuses for a game ever found on the Spectrum.
Check out Wikipedia's Entry about this competition

Previous Competitions

Want some inspiration? Look no further than entries from competitions from yesteryear