I have met a handful of Americans in Ibiza. All the ones I met were traveling on their own and very knowledgeable about the DJs who they had specifically come to see.
Its not the 'kerazy "Wild on..." experience you may have seen on TV( which is equivalent to the 'Ibiza uncovered')
There is a lot more to Ibiza than the 'crazy partying'. When you go, hire a car so you are able to check out more of the island, the great beaches, small towns etc.
What club nights are you planning to go to? In the clubbing guide to this website, the party calender gives you a list of who is at what clubs at certain nights.
Hope you have a good trip!