Mexican Food in Tucson
My personal favorite it Boca on Speedway. I LOVE the macho taco. It is an anaheim chile stuffed with melted cheese and steak. Maria, the chef/owner also makes really creative salsas that rock...you get 6-9 each time you dine. ie banana habanero; green apple, coconut milk, chipotle.
Another good place is Taco Aspen. I have not tired the truck, Aqua Con Nene but I hear great things.