Haneisen has an ad at KS for black milks:
http://market.kingsnake.com/detail.php?cat=59&de=720862
Can't vouch for these folks...
http://www.freewebs.com/dnsreptiles/availablesnakes.htm
Or these guys:
http://www.kingsnake.com/Isisreptiles/
Jim is a good guy, I bought a Pine Snake from him earlier this year...I don't think he has any BM's right now...
http://www.homegrownherps.com