I've been all over the country and I've never had better tacos. Barrio is the place to go for tacos, queso, guac, and margs. It is relatively inexpensive and fantastic. There are four locations currently around the Cleveland area, I have been to 3/4 and had great experiences. The tacos are build your own tacos and are only $3.00 each. There are specialty tacos as well that are $4.00 each. The queso blanco is my favorite appetizer to start off with. The traditional guacamole is also good. Their chips are always warm. There are also specials of different kinds of tacos, guac, and queso that changes on a monthly basis.
Their margaritas start at $6.00 a glass (an extra $1.00 to add a flavor) and are delicious favorite flavors are mango and blood orange. Their are also seasonal margarita flavors as well. If margaritas aren't your choice of drink there is a full service bar that can make you whatever you'd like.
Caution here, they do not accept reservations and this place is always busy. If you are going just for the restaurant make sure it is not before or after an Indians or Cavs game or you could be waiting upwards of an hour as the restaurant is not that big.