Here is a list of walkout music for UFC 164 in case you are trying to hunt down a song you heard at last nights event. I was a fan of showtime's walkout song.
“Showtime” by Tum Tum feat. Jim Jones on th e “Evil Empire – Be South 17″ Album
“Awesome” by R-Swift on the “Anthem” Album
“The 4th Crusade” by Bolt Thrower on the “The 4th Crusade” Album
“Amazing” by Kanye West on the “808s & Heartbreak” Album
Full List: UFC 164 Walkout Songs Guide