I'm not sure what you have in your grocery stores in Mexico, but up here, I found a solution to my barbecue ribs crisis. A number of companies pre-cook them and then shrink-wrap them. You just buy a package or two and all you have to do is heat them up (they already have the barbecue sauce on them) on the grill for about 5 minutes each side, over hot coals. I tried this 2 weeks ago, and they came out yummy!! And, it was so easy!!
Oh, they also come out good in a crock pot (not the pre-cooked ones, just the regular ribs you'd buy at a market), but the crock pot version doesn't have the same sort of "grilled" texture as cooking them on a grill.