Sniff, you're making me remember all of the things that I miss so much about Austin.

For both trail riding and trail running, there's the Barton Creek Greenbelt right by downtown. It's lovely in february and the creek should be pretty low at crossings so you shouldn't have to go wading. There are rock cliffs there for rock climbing and all sorts of neat things to look at, right in the center of town! Afterwards, you can stop by Barton Springs pool right near the trailhead- it's a massive spring-fed (constant temperature) civic pool with a natural bottom and some salamanders that only live in the area right around the pool.

There's a hard-pack gravel surface trail that goes around the river in downtown for gentle riding and running, it's a real favorite of runners here. I do believe that the marathon uses it in the course. Say hi to the statue of Stevie Ray on the south side of the path for me!

Bicycle Sport Shop on Lamar rents bikes of just about any sort, I think they list all of the details on their website, bicyclesportshop.com . 360 Cycleworks runs an amazing Sunday morning ride out through west Austin and over the dam, it's one of the fastest ways to see the sights. The pack ranges all the way from pro riders to n00bs and splits apart accordingly. All of the bike shops should carry the Austin Bicycle map, which costs a few dollars and which is a great map for the purpose.

As for food, Austin has some of the best. Downtown near 10th and Red River, there's a mexican restaurant called Serrano's that's in a neat old house with a plaza outside where the symphony plays. They have superb salsa and margaritas and you should definitely have a meal there. You also have to get breakfast tacos- one of the good spots is Taco Shack, which has locations lots of places including downtown, near the convention center. The ones from the trailers are also usually excellent, you just have to know some spanglish

I'll second Pedernales Falls as a park you should go to. The falls are beautiful and the primitive camping area is one of the best in the area to explore. It's about 30 miles west of the city and makes about a 40 mile each-way ride; email me if you want a route suggestion for a day on the bike.