I don't know much about Irvine, but there's a few good places here in LA. Father's Office is probably the best known, there's also a decent bar (at the end of my street actually) called The Village Idiot that might be worth checking into (they often have Pliny the Elder if you're into that) though it doesn't really have a fantastic selection. It's kind of a beer wasteland here (San Diego is a whole different story if you can make it down there). Both places have good food (Father's Office is known as having excellent burgers).
If you go to any Whole Foods here, they have a pretty amazing beer selection. I don't know where you're from, but I know they carry a lot of beers that aren't readily available in some parts of the country. There's also a beverage warehouse called BevMo that carries a good selection if you're looking for things to take back with you.
If you make it out to Silverlake, there's a microbrewery/restaurant there called Good which I like.
A quick google search should help you locate any of these places.