Español is beautiful and one of the important world languages. Also it makes sense to learn spanish if you are traveling or living in Spain. Even in the metropolis Barcelona many people do not speak english. In smaller towns you are lost without any knowledge of spanish.
Small language excursion: in Catalunya (of which the capital is Barcelona) locals speak catalan and spanish as a second language. If you want to live here for a while, you have to face learning catalan additionally. Although in general people are willing to speak spanish with tourists and foreigners..
You can find language schools like sand at the Mediterranean. Also here they like to earn a little bit more and prices are very different. If you stay for longer and have a small budget I recommend the International House. They offer courses made by teachers in education which last a few months and are very cheap. Attention: you have to apply with a test before going. If you are lucky they will select you for one of the classes and you save a lot of money. Be there for the test punctual (or even ahead of time) because the lines or usually long. The quality of the course is obviously not sky high.
If you do not like to invest that much time I have a recommendation from friends for you: Speak Easy. I heard the quality is good and the price tag is fair. Here you can get some spanish on a weekly basis.
Additionally to all of that you can find free spanish courses in the internet, like the BBC – Learn Spanish with free online lessons.