Hi Flavia
If you want good cheap accommodation your best bet would be to stay in San Antonio town or bay, or Playa d'en Bossa. These resorts are more catered towards the tourist, and if you are on a budget prics may be more reasonable. Clubs are close to hand in these resorts, San Antonio has Eden and Es Paradise, and Playa den Bossa has space. Buses are really regular to take you to the othe clubs which are futher out, such as Privlege, Amnesia etc, and public transport is really cheap.
San Antonio has the sunset strip, and other cool bars like bar M......the last time there was lots of pre-club parties held in these bars which cannot be missed! Staying in San Antonio Bay myself this year....good luck, I hope you make the right choice!