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Childcare in Austin, Texas: Weslake Childcare. They're on Bee Caves a few miles west of Mopac so they're probably on your commute path. My son (currently 6 mo's) has been going there for three months and he seems to really enjoy his time there. Among other things, they're one of few places that is willing to use our cloth diapers, and they also have a caregiver who helps teach sign language.
Another option is the Eanes school district daycare. I haven't researched it much, but it is highly recommended by a couple of my co-workers. I think they are located at several of the Eanes elementary schools including Valley View near 360 and Bee Caves.
Edit: after googling around a bit, I found a webpage for the Eanes school district childcare program. Unfortunately it looks like they're discontinuing their infant/toddler program this summer.
Community Education - CDC/ELT