If you have signatures only, Edward G. Robinson is worth $100. Gene Tunney is also worth $100.
If those are the only two autographs that you own, you have the start of a great collection. Gene Tunney was a world boxing champion who retired undefeated as a heavyweight. He beat Jack Dempsey twice, which was a big deal at the time.
Edward G. Robinson was one of old Hollywood's great actors. He was particularly good in gangster roles.