Data/Event Logging and Analytics

I am looking for a PHP system to handle both the data collection and analysis of general user actions on our site. I want to track things like "items searched for(text entered)" in correlation to items found. We have a guessing game - I want to track incorrect guesses for each game, I want to know number of guesses to get it right, number of points awarded per phrase... As you can see - this needs to be a pretty abstract data collection and a programmer friendly way to answer new questions. I don't expect the reporting to be user friendly, I expect to have to program new logic and reports to answer questions. However, I do want this to be more than just down and dirty log and answering just the example question above. I also want consideration in the solution for multiple servers being possible in collecting the data, the reporting should be separate and bring all that data together. There should be minimal load on the data collection so we don't impact the server performance. The basic site in questions is [login to view URL] The game that is generating much of the current traffic is [login to view URL] This game is used by many clients - ie reference into this game. I need that as a factor in the logs as well - ie references to our content from our partners...