Go to Barcelona.. It is a beautiul city, Spain is one of the cheapest countries of the EU. This city is amazing...
Plenty of museums, art galleries and theatres...and of course shops. If you love to shop for art try all the fantastic shops on the streets around the Picasso museum.
The main Las Ramblas that everyone raves about was tacky and cheap and the restaurant we ate in was third rate. By night it is just a red light area. But do wander down all the side streets which lead you to designer shops, squares, cafes and markets.
The Olympic stadium is worth a visit and do visit the marina area and walk along the marina front - it is beautiful.
Panyvino, Consolet del Mar, 15 08003 Born ( 93 268 77 76) - home cooking and inexpensive
Thai Gardens, C/Diputacion 273 08007 (93 487 98 98) - expensive but lovely dining experience
Puttanesea, Gran Via de es Corts Catalanes 618 (93 342 41 74) - if you fancy an Italian
Obviously an abundance of tapas restaurants everywhere - but avoid eating on Las Ramblas!
You have to visit Parc Guell - the Gaudi creation which is very beautiful. I recommend you go there at your leisure rather than on a rushed tour!
Have a great time!