* * Various artists, "I'm Your Fan--The Songs of Leonard Cohen," Atlantic. Looking for a worthy tribute album to songwriter extraordinaire Cohen? Go back to Jennifer Warnes' recently re-released "Famous Blue Raincoat," not this ill-compiled collection whose 18 acts--most of them English, all of them male--sound, in their studied dispassion, remarkably alike. Cohen die-hards will have slight fun picking through the selections--including standouts (such as they are) from R.E.M. and Lloyd Cole--but novices are unlikely to figure out what the big deal is from this dull primer alone.