Since the courts are a ways off the road and down a grade, you can't easily see them from the road. If you turn north at the first driveway east of the Zilker Botanical gardens on Barton Springs Road, you should be able to see them. If anyone can provide more precise directions, please submit them!
The competition ranges from recreational slop on court 4 (the west-most court) to high-level doubles play on court one. Most courts have acceptable nets, but no boundary lines. Warning: Court 3 has a large, hidden rock (or slab of concrete!) buried in its shallow sand. The other 3 courts have no hazards as of my last visit.
Aussies also has a variety of leagues throughout the warmer months. Call for their open play schedule.
Volente Beach opens at 11am daily, and closes at 10pm weekdays and 11pm on weekends. $4 daily admission gives you access to the swim area, picnic area, 3 lighted pro beach volleyball courts.
Carlos 'N Charlies is located on Hiline Rd. near Emerald Point Marina on Lake Travis. To get there by land: