Well, I tryed some researching for a while ,and luckly got some results
You can get the Al MacInnis through the Blue's address ,but the chances are slim to none cuz he is such a popular player
Rick Ankiels, Im not sure (couldn't find any thing on him)
For Vince Carter ,you could try his fanmail site ( not a friendly guy so might not sign)
Vince Carter
c/o Embassy of Hope Foundation
PO Box 9596
Daytona Beach, FL 32120
USA
Any points donated to me would be appreciated