Good timing! I was just about to post on Tamarindo.
1) Pedro's for simple, good, inexpensive seafood. It's in town, and is basically a shack, with some picnic tables under a tent. The fish sometimes gets overcooked, but it's good quality seafood. Portions are huge. The seafood stew (which bears a strong resemblance to bouillabase) is delicious. And the onion rings are fantastic. It's BYOB. If I had known about it the first night, I probably would have gone there every night for dinner. Under $10/pp.
2) Someone had a good pineapple pie. Unfortunately, I can't remember if it was Nogui's or Monkey Club. It had a buttery crust, and caramelized pineapple. Damn, i wish I'd taken notes.
3) One of those two restaurants also topped good quality seafood with one of the worst sauces I've ever had. I wish I could remember. Well, if you go to the restaurant, and there are various permutations of proteins and sauces (I think I ordered halibut with a pepper sauce, expecting a sort of roasted pepper salsa, and got a roux-based white sauce with canned jalapeno - I noticed they also offered the same sauce with steak), you can opt not to get any sauce. Don't want to libel anyone, but I don't want anyone to have to suffer through that sauce either.
3) Etc. was kind of upscale, and had good quality seafood. I would avoid anything described as "garlic crusted", unless you really, really love garlic. Good chocolate souffle, in case you're suffering from bourgie withdrawal. Figure around $20/pp
4) Frutas Tropicales (across from Witches Rock Surf Camp) for satisfying cheap eats. It's open air seating, which means you get hit with the exhaust of vehicles going by, but it's worth it if you're just after arroz con pollo, or a chicken sandwich. Oh, they have good fresh fruit juices too. Less than $5/pp.
Oh, I had a decent ganache tart from the French bakery in town. They also had some tasty looking empanadas, which could make for a good light lunch (I didn't get a chance to try them).
I am in Jaco Beach, and it has an iffy reputation for soem people, but I like it to just chill out (you wouldnt believe how SLOW the internet connecytion can be, but it helps the chill factor). Have eaten at LOS AMIGOS twice (on the main street, they have flaming tiki torches at the entrance.
Its alittle pricier than those around it, but the qulaity is excellent. Lots of Thai themed recipes, and the only place I have known to have onion rings!!
Also on the main street is Mikes pizza place, used to be called Killer Munchies, now called Rio Asses. So so pizza, but them I am a real stickler. Better than the Pizza Hut franchise by leaps and bounds.
Best for the adventurous is to head to the local "sodas" good food for the most part, and dirt cheap, but huge portions.
Breakfast places just arent worth getting out of bed for. The local farmers market is on Fridays, at teh airport street (where planes used to land, but now dont) Mas X Menos is the local grocertia, but has just been bought out by WALMART of all orgs!!! Not a good trend. There are thousands of condos being built by rich American developers, so the quality restos cant be far behind.
I just want to report that my trip to Costa Rica was phenomenal. Even though we mostly ate at our little Inn, my whole crew was enamored by the fresh fruit and seafood. It's different flavor experience knowing the fruit you are eating was ripened on the tree/vine, instead of cut 2 weeks prior, shipped to your state and ripened in "hot" room.
The dorado, ahi and sea bass is what we ate almost everynight... and Rice and beans with every meal is something i miss now stateside.
Frutas con leche was always refreshing in the middle of the day...
I can't wait to go back to CR.