By "next week" do you mean SXSW? Because probably the popular spots are going to be absolutely packed, and your best bet will be using your connections to get invited to sweet-ass parties!
There's some good TexMex in Austin (very different from California version of Mexican food). I can't come up with a name at the moment - my coworkers always take me to a different hole in the wall when I'm there, and it's always awesome. There's a great vegan place just south of the river called Casa de Luz. It's a chain, but I like going to Saltgrass Steakhouse when I'm in Austin. Amy's ice cream. A bunch of bbq options if you can't get in to Franklins...
There is the most amazing ice cream place on Duval street, inside Juiceland called "sweet ritual." It's all vegan ice cream, but don't let that scare you off. I had it over the weekend and I'm not exaggerating when I say it was the richest ice cream I have ever had.