Arrays and Drop Downs

Hey there, I dont know how simple this one is, but I'm trying to create a form that utilises a series of arrays and, with drop downs, select the record for that row, printing it out automatically and calculating various functions attached to these records.

Quite simply, how do I get the drop down info to then refer to, and so retrieve the items from, an array by the same name without using a very long list of if... statements?