I've been watching James Garner--mostly on television--for a decade or more and while I was cruising the Internet I bumped into four titles--with trailers currently available--that I was unfamiliar with. It's probably no coincidence that these were all released before I was born.
1970. A Man Called Sledge. This is James Garner Spaghetti Western. It also starred Dennis Weaver and it was directed by Vic Morrow. It really looks pretty great.
1966. Marlowe is based on Raymond Chandler's novel The Little Sister. James Garner plays the legendary Philip Marlowe in a less than conventional manner. I'm still not convinced this is Jim Rockford.
1960. Cash McCall. This appears to be a romantic comedy. It was based on a novel by Cameron Hawley and it co-stars a young Natalie Wood.
1959. Up Periscope. This film was based on a novel written by Robb White and it stars James "Maverick" Garner. It looks great.