As Im currently in Cork and have left my guidebook and half of everything else in Dublin I wont be able to name all the places I visited but here are a few photos anyway. I recommend wandering around town at about a quarter to nine and if you see somewhere with a queue of Spanish outside its probably a good bet. I also recommend eating the local food, fish is an excellent option, Steak and Chips is what they feed tourists and wont be great.
Tapas 24 is definitely worth a visit, apparently the guy who is head chef here used to work in El Bulli (I may have this story very very wrong but thats what I was told). There was a queue out the door, the tapas were good, the staff were utterly ignorant and as long as you know the Catalan for tripe you cant go too wrong. Really though, yummy tapas (none of which I was able to take a photo off without a good forkful of first) and good wines.
You can however get tapas pretty much everywhere in Barcelona although they arent native to here and I did prefer the ones I got last year in San Sebastian.
One other thing you really have to try is the hot chocolate although its rare enough that the weather is cold enough for you to want to drink semi-solid chocolate. If the weather isnt warm then this will definitely put a smile on your face. (NB. Its not true what they say about the rain in Spain and planes). A cup of this between 2 will do the job unless you havent eaten in 3 weeks.
If you are planning a trip one thing I can definitely recommend for saving your weary feet is to rent a GoCar. This is probably the closest to a noddy car that you will ever drive but is a good way of seeing the city as long as you can handle the constant wolf whistles and bursts of music it emits as you drive down busy streets. You would not want to be easily embarrassed as almost everyone you pass by waves at you. Unlike bus/bike/walking tours where you have to listen to someone tell you and a bunch of others all about a city you get to chose what you want to do and see with this little car even if you decide to go a bit off your original track. It has GPS and a little talking voice that tells you where to go, what you are seeing and places to eat in the area which really allows you to see so much more of a city than you normally might.