I found all the info on the 2 reported MMA fatalities, Douglas Dedge and Sam Vasquez.
I also found this really sweet MMA injuries vs. boxing injuries listing in the Journal of Sports Science and Medicine from 2006.
http://www.jssm.org/combat/1/18/v5combat-18.pdf
It is a PDF file.
UPDATE!!
finally found a punch statistics website. Compubox. This is a link to the De La Hoya vs Steve Forbes fight May the 3rd.
CompuBox - Every Punch Counts
vs the MMA version called CompuStrike
CompuStrike Stats