It depends where you are. The more touristy places are obviously going to be more expensive.
I live in Manilva town which is not touristy and is more Spanish, a couple of km from the sea front. I pay around 1 euro for a small beer, so say just over 2 euros for a pint. If I go down to the sea front to Duquesa, more of a tourist/ex-pat place, it´s 3-4 euros for a pint of the local Spanish beers.
I was in Barcelona recently and was paying 2.50-3 euros just for a half pint and shockingly 7 euros + in Barcelona´s Olympic port area.
Restaurant prices are similar to the UK, but tapas can be a cheap way of eating.