It was at one of those nightspots where Angel and Buffy creator Joss Whedon discovered Andy and cast him as Lorne (short for Krevlornswath of the Deathwok Clan), a friendly demon who just wanted to sing. He could also "read" people when they sang, being able to tell what's really going on with them.
Though I've only seen seasons 1-4 so far (I'll be watching season 5 ASAP), I really enjoyed the three-part arc at the end of season 2 which featured Lorne, Angel, and the gang heading to Lorne's homeland of Pylea to rescue Cordelia. At the end of part 3, I commented to my girlfriend (a big-time Angel fan), that the cast, crew, and writers were firing on all cylinders with that arc!
Our thoughts and prayers go out to Andy's family, friends, cast mates and fans. To die of heart disease at 33 is just too sad. His father was at his side. Rest in Peace, Andy.
Source: IMDB, Cinema Static