I have been sending TTM's since April and I have gotten well over 100 back so far. I signed up on sportscollectors.net to see who signs and also I can track my successes and failures. I think it costs $15 for a year.
I also ordered the Harvey Meiselman lists as well to help find some of the harder addresses.
I send to almost anyone that I have a spare card for. I have got some good returns. I will admit that there are a few I paid the fee for as well.
I also put up vidoes of my returns on Youtube. Here is a link
http://www.youtube.com/playlist?list...2&feature=plcp