From Sinatra it's either The Lady Is A Tramp or Don't Be That Way. But there's a ton of other good stuff like that from the 60s, like Bing Crosby, Brenda Lee, Etta James, etc. Check out Lenny Williams too! He's more popular in the 70s but I think he's little closer to the style of the 60s- just different enough to be something fresh for your ears and similar enough to pique your interest :)
