The idea was to create individual baseball cards that utilized designs similar to those used by baseball card producers. With about 20 concerts each summer, there were about 80 cards by the end of the 2014 season. The front of the cards have the date of the performance, while the backs mimic early baseball cards with information about the performer..
The Mann Center for the Performing Arts opened in 1935 and seats about 14,000. So I am sure there are plenty of cards out there, just haven't seen that many of them...
(Topps 1968 design)
Phish 2014.07.08-09 (Donruss 1987 design)
reverse of the July 9 card
the reverse reads "You are holding an official installment of an art project by illustrator Alan Fine for the Mann Center & AEG Live commemorating select events each season at the Mann. For a full listing of concerts at the Mann visit Manncenter.org. Thank you for your support"
I found the two Phish cards on ebay, where there are several cards available for under $10.00 each. Other images found on the internet include....
Bob Dylan 8.17.2011 (similar to the Topps 2003 design)
Ray LaMontagne 9.30.2011 (Topps 1976 design)
Alan Fine listed this card as his favorite to create
The Monkees 7.20.2013 (Topps 1962 design)
Norah Jones 06.28.2012 (Topps 1989 design)