How about Carne Asada?
http://www.alanskitchen.com/MAIN_DISHES/carne_asada.htm
or
http://bbq.about.com/library/rec/blb90930a.htm
or
http://www.mexconnect.com/mex_/recipes/list/crnasen.html

Marsha/Ohio

Spanish tortillas (absolutely NOT to be confused with Mexican tortillas)
are also traditional (and delicious), but would definitely not be low
carb (they're basically potato and egg omelettes or frittatas).

Paella would also not be low-carb, because of the rice.

"Tapas" is just a word that refers to small plates of foods - sort of
like appetizers, though often a meal consists of just a variety of Tapas.
I'd focus on those, and  just make a variety of different ones, such as
chicken, fish, pork, shrimp, etc. - then maybe some made from relatively
low-carb veggies, such as mushrooms.

I don't have any specific low-carb recipes, but here are a bunch of links
for Tapas recipes or just Spanish recipes in general - It looks like
there are a lot of recipes like "garlic prawns" or "garlic chicken" that
appear low carb.

Tapas recipes:
http://tinyurl.com/2g5le
http://www.tienda.com/recipes.html
http://fitdv.recipezaar.com/r/chef=52543
http://www.ericweisstein.com/fun/wine/tapas.html

Spanish recipes:
http://www.recipesource.com/ethnic/europe/spanish/
http://www.cbel.com/european_recipes/

Good luck!