Correct list of composers in dropdown iTurns composer list: I accidentally entered my own name with two spaces

I. pulled some of my own music into iTunes, but when I was entering my name in the composer field for the first time, or at some point, I entered two spaces, so that my name shows up with two spaces. How do I correct this? For that matter, see how I've entered myself in lowercase as well? I'd like to eliminate those options... do I have to hunt them down throughout my iTunes library? Or is there a simpler way? Thank you.