MonteCarlos (next to Adelitas) has good food. Some nice eye candy too.
However, the best food in Tijuana isn't in the ZN or downtown. The best places are in Zona Rio or on Agua Calientes (near the Tijuana Grand Hotel.)
On another site I've reviewed a lot of the high end restaurants in TJ. IMHO Tijuana has some first rate restaurants that would hold their own in any American city.
You asked if you'll find "American food." I think that depends on what you consider "American food." You probably won't find meatloaf, turkey, etc. but you will find American fast food, steak, pizza, etc. If you want "American food" you can try TGIF Fridays, Applebees, or Bob's Big Boy plus any of the places serving US fast food. You will also find some excellent Contential food as well as Chinese, Italian, Japanese, Spanish, and Greek food in TJ. (Komasas is my favorite for sushi.)
Here's a list of a some "upscale" places well worth visiting:
Villa Saverios
Chans
Komasa
Rivoli
Ferro de Mazatlan
Pampas
Grand Bisto
Fono Argentina
Casa Placencia
La Costa
Since you are going to be in the ZN and hence near downtown try La Costa on 7th between Revolucion and Constitucion It has some decent seafood; I recommend the filet of fish olivia.
If you must have "American food" on Revolucion you'll find Burger King, KFC, and Carl's Jr.
Tj has more to offer than just the Zona Norte. Good food--at decent prices--is one of many finds tourists can enjoy while visiting Tijuana.