Your idea of Mexican food (since you're from Mexico) is probably different than American's idea of Mexican food. Mexican food in the US is predominantly Tex-Mex or Cal-Mex. It's my understanding that you'd be hard pressed to find a Chimichunga in the heart of Mexico (unless you were at a resort town). I could be wrong though.
Tis' true. Don't get me wrong, tex-mex has its place and is super tasty, but authentic Mexican food is really different, apples and oranges, really. I would dare to say that many Americans would find many authentic Mexican dishes rather unappealing, simply because of the meat ingridients. Take the ubiquitous taco for example; tacos de lengua (cow tongue), tacos de cesos (cow brain), tacos de tripas (beef tripe), and tacos de cabeza (cows head) just to name a few. Of course, for the picky eaters there is always carne asada.
I love mexican food. We have some non-authentic fast food places around where I live (rubios, chipotle, la salsa), and I like rubios and chipotle a lot. La salsa needs to go back to culinary school and stop putting rat droppings in their burritos.
I've been to authentic mexican restaurants before and by far they are the best. It would be expected, they make stuff fresh, they pile on a ton of add-ons (beans, rice, veggies) and it's healthy to boot! I forget the name of the restaurants I've been to, my ex-gf (who was 1/2 mexican) used to take me to 2 places.
Edit: One of them was Anita's and the other one was La Tapatias (I think that's the correct spelling). The latter was especially sublime. Food there is delicious
I live fairly close to Postville, a somewhat unique town in Iowa that has a number of Mexican immigrants.
(Sadly also the place of the largest immigration bust in the US I think.)
Some of those immigrants opened up a number of Mexican restaurants, including in Decorah, and the food is just fantastic.
In fact, I'm heading to one right now for lunch.
When I was in Plano, Texas I ate in a restaurant called Abuelo's. Good food, nice decor. I think they have a location in Florida as well, but it's a bit of a drive.
I've never wandered south of the border, but most of my favorite Mexican food places are always getting busted by the health department and immigration control, so I assume it's close enough.
I use to eat at a place in Whittier California called Burrito Track. It was ran out of an old 1950's ice cream parlor. It still had the fiberglass ice cream cone on the roof, they didn't seem to care. I use to love getting their chicken tacos. They'd give you a plate with 12 grilled corn tortillas, double stacked for 6 tacos, with their picked apart chicken (not diced, but not shredded either) that was simmering in a pot with their marinade on top, with cheddar cheese and lettuce. The plate would be piled so high, you'd think it was actually a taco salad. It took some work with the spork to separate the pile into tacos.
But only if done properly, on a vertical spit, with onions, and a pineapple on top. 
