Ollie Joe Prater, 44, the rotund nightclub comic who was a favorite of patrons of the Comedy Clubs in Hollywood, La Jolla and Las Vegas. Prater, who also had done videotapes, was a frequent guest on the "Tonight" show. He got his start in the late 1970s at the Comedy Store West in Westwood and moved to the Hollywood Comedy Club where he regularly followed Richard Pryor on the bill. He also appeared in nightclubs across the country and was a featured performer at several Las Vegas hotels. In Albion , Mich., on Monday of the complications of a stroke.