Not in Austin but went to UT there. Lady Bird Lake in downtown has some incredible bass fishing and some great views to go along with it. You can catch some beastly sunfish on the bridge pilings and on most of the man-made docks, buildings, walkways, etc. For both shade is your friend until the sun gets low, shade on deeper water = $$$. Points, especially where the creeks flow in are excellent once the sun starts to go down. At low light start throwing your favorite reeling lures (cranks, spinner, etc) and find where they have moved in to feed, find them and not uncommon to catch a dozen 1-4 pounders in an hour. During the day use plastics with a lot of action - curly tail worms or creature baits and throw them to shore in the shade and work them back out. Work them fast since the water is clear, its better to go for any aggressive feeding fish that way.