Thought i'd contribute to this as well as i also send out cards mostly during spring training. heres my list that i did so far this year.
I sent out to:
Ken Griffey Jr.(very long shot but a personal friend of mine was his grandfathers coach in high school in 1938, i added that in the letter hoping it may help my chances.)
Well i got my first one back Tuesday:
I was very surprised to see it in my mailbox, but very happy with it