Drink: Happy Ending Cantina - Across the street from the Marina, ask any cab driver and they'll get you there. Cheapest drinks i've found there... 2 beers, and 2 double-shots of tequila for $5, $5 margaritas, etc... Owner is an american, all the bartenders are really cool people
Food: When I was there, i had fantastic tacos of all kinds (fish, carne asada, carnitas, etc...), decent lobster, argentinan steak, place that specializes in carnitas, fantastic breakfast (most places are where locals eat, i didn't eat at very many "tourist" places.) Just tell me what your looking to eat and I'll tell you the name and how to get there
Also check out tripadvisor.com