Off the top of my head:

Non horror--James Cagney (I have all of his films, either on VHS or taped from cable or DVD).
Complete Chaplin and Keaton collections on DVD and 16mm.
John Wayne is probably the largest collection; I'm close to having the complete filmography.
Orson Welles is complete (with a couple of foreign DVDs, like Chimes at Midnight)
All of Olivier's films.
All of Laurel and Hardy's films (including silents) that have been made available. DVD and 16mm.
Marcello Mastroianni (about 15 titles)
Jack Nicholson is complete up to the last DVD release.
Johnny Depp is complete (including 21 Jump Street --no kidding!)
Cary Grant is nearly complete--missing a couple of early films.
Bette Davis is complete (like Cagney, a mix of taped VHS from cable)
Katherine Hepburn is nearly complete.
Douglas Fairbanks (about 8 titles)
John Barrymore (about 12 titles)
Anthony Quinn (about 12 titles)

Horror--I have everything released in the US on DVD starring Karloff, Lugosi, Cushing and Lee.


That's all I could think of--these are just my favorite actors.

Mark Redfield
www.redfieldarts.com