I worship at the temple of the BBQ Gods, wife not a big fan but wiling to indulge me as long as she can have an alternative. Anybody?
I would check out Texas Monthly's special bbq section of its website: http://www.texasmonthly.com/bbq
They have lists, rankings, and a lot more information, with lots of bbq places in and near Austin. Also, they may not have Salt Lick in Austin on the list, but it is really good.
A bunch of friends spend time in Austin every year at SXSW. My foodie friend Emily has a roundup of some of her favorite bites and sips of last year. http://mouthoftheborder.com/2011/03/legit-delish-austin-edition/
I have been to Augie's Barbed Wire Smokehouse in San Antonio many times when visiting my daughter and it is a favorite. I agree with bexcahlik, registering with Texas Monthly will make your searches much easier. http://www.augiesbs.com/
A short drive south of Austin to Lockhart would be fun, there are two BBQ places there in the quaint little town. Check my blog: https://midnitechef.wordpress.com/2011/06/12/nites-out-bbq-and-classics-in-lockhart/
Definitely Salt Lick BBQ in Austin. Then, head to South Congress food trailers and get a taste of goodness - dont forget to end with Hey Cupcake!. Kenichi Sushi downtown, Sulllivans Steakhouse downtown as well as our favorite "occasion" place, Eddie V's (Downtown and Arboretum locations). Gueros downtown is a great mexican food place, where the "stars" sometimes hang out. Don't forget Amy's ice cream (various locations) ENJOY - PS Steiner Ranch Steakhouse, and the Oasis offer perfect sunset occasions of Lake Travis.
Amy's is not to be missed. Get the Mexican vanilla. Justine's is a nice out of the way French bistro, adorable. And they might be in many places but the Torchy's tacos are really good, nothing like a homemade tortilla to make all the difference.
Oh and it may be status quo but PLEASE if you like a proper cocktail head to the The Driskill. It will not let you down.
Yes, to all the above, and add:
San Antonio: El Mirador, Rosario's, SoLuna, La Fogata
Austin: Takoba, Fonda San Miguel, Uchi and Uchiko, Mandola's
Breakfast tacos in Austin: order the Diablo salsa with your Torchy's taco, Juan in a Million, Tacodeli, Maria's Taco Xpress
Current BBQ white-hot spot: Franklin BBQ (they sell out by noon)
See it to believe it: Whole Food flagship store, with many dining options
My 2 cents for Austin! Happy hour at the bar at Jeffrey's, wine and snacks at Mulberry (they have Dymnamo's wine there!) french fries at Hyde Park, GIANT beef ribs at The Ironworks (beware - no AC - but a big fan and cold beer) treat your wife to vegetarian at Mother's then amble across the street to Antonelli's Cheese Shop, Chuy's for Tex Mex (the South location has more seating) and if you want to fancy it up head out to Hudson's On The Bend one evening for a truly amazing dining experience. Drive down south first for even more food trucks (in clusters, they are scattered everywhere) and check out Barley Swine for the hottest New Chef around!!!
San Antonio is limited for BBQ, but as a former native, try Liberty Bar, El Mirador, La Fonda on Main, and Cappy's on Broadway. If you don't mind dives, Blanco Cafe has some of the best home cooking Tex Mex in San Antonio. Try the location near downtown...not the Northside location. The best home made tortillas in town.
As a former Austinite also, you will LOVE Blue Dahlia and East Side Cafe. East Side has their own garden and both are as organic as possible.
When I was there last month, all my foodie friends told me Franklin's was definitely THE place for barbecue. Only open for lunch, and does not take reservations. However, it is downtown, and not out in the sticks.
The Hey Cupcake is really great. I don't really care for cake\cupcakes and I gobbled mine in 5 bites. If you do go to Chuy's be sure to ask for the creamy jalapeño - it's not on the menu but it will go with any and everything you order. I have been perfecting my own version for years now. My spouse is presently swearing by those Hyde Park fries, and he says to ask for Vince as your waiter.
As a current resident of San Antonio, I will attest that all of the above suggestions are solid. Regarding BBQ, in addition to Augie's, you need to try the Smoke Shack. It's a food truck that's got a ton of local buzz right now. You can find their current location online (congercatering.com) Saturdays, they are @ the Pearl Farmer's Market. Have Fun!!!
Go to Perla's on S. Congress and get the grilled brussels sprouts. Amazing! also, sit outside under the breezy, mister things. Fabulous!