I studied in Spain for two months last summer, both in Madrid and Alicante.
The key to finding a place you'll enjoy, is to get all the information possible.
Madrid is a wonderful city to learn in, as there are things to do and see every day. I studied at the Universidad Compultense. Although I thought the courses were interesting, the school itself was not the greatest as far as facilities were concerned.
Alicante was wonderful. The city is great and the school was incredibly beautiful. They had a great summer program, with lots of European as well as American students. They have a website,
www.ua.es that can probably help you with more information. I'd definately recommend the school.