I went to check out the marketplace on N. Lamar that was mentioned in the Austin Chronicle a couple of weeks ago. I'd advise going there on the weekend instead. Not much was open.
But on the way back home, I passed El Taccorido, a nice shack in the parking lot at 9316 N. Lamar. I don't have any idea how long it's been open, but it's the first time I've seen it.(I don't know the cross street, but it's in the shopping center with Shalimar's Indian restaurant.)
I had two tacos--carnitas and pastor. Both were excellent. The salsas were also quite good. And the price was right--two tacos and a Jarritos for $3.75.
I only wish I lived closer so I can try their breakfast tacos.