I am not the autograph collector I once was, but I have always found it interesting to send and receive signatures through the mail. There are some things to know when pursuing such a venture, but know that most athletes are busy and it may take some time before you get a response.
I have had some success with some of the bigger name sports stars, but I will also include a list of guys you should not even bother with.
Note: Please be respectful in your autograph request and try not to send mail to the personal address of the stars. I find this distasteful to a degree.
Joe Mauer is one of the friendliest guys in sports today and he is always willing to sign a card or ball from a fan. Mauer has signed several items for me in the past and has even written thank you notes back, which gives him an A+ in my book.
Drew Bledsoe was one of my favorite quarterbacks growing up and when I got into the hobby of asking for autographs through the mail, Bledsoe became the first to reply. I sent out a card and photo and one week later received the items back, along with a game-used wristband and a personal letter wishing me luck in the future.
If you are seeking autographs, this is one guy to write too.
Cal Ripken is a legend on the diamond and also a legend in the minds of those autograph seekers. Ripken is very down to earth and will sign about anything, unless you accidentally send him a Billy Ripken card.
Ripken does receive a ton of fan mail, so there are sure to be some delays, but most of the time, you will receive a signature.
Malcolm Kelly may not be a major star, but he is kind in his offerings as far as autographs are concerned. I included Kelly on this list because he sent me back much more than I sent him. I sent Kelly a couple of cards and a Redskins hat and received the cards and hat along with a pair of game used cleats and tickets to a Redskins game. That was amazing in my opinion.
Matt Hasselbeck is one of the first autographs I seeked at one time and was also one of the quickest to reply. Hasselbeck is kind an courteous and will sign for his fans.
While I am not saying these guys are bad at all, they are the ones who usually will not sign autographs through the mail. Many of them have their publicists send the items back with a note stating they do not have the time to sign autographs or they charge a fee.
Pete Rose - Charges 50 Dollars per signature
These were a couple guys who sent rejections over time, but if you like to collect autographs through the mail, this is a good list of stars to avoid.