Installing iTunes on an External Drive

I have a WD passport portable HDD, on which I backup/store all of my music (I bring it with me and use at a radio station where I'm a volunteer DJ). I plug it into the radio station's PC via USB, and while I can use Windows Media Player on the host, I prefer the search/sort/layout available via iTunes better. iTunes is NOT installed on the station's PC. So, the real questions is: Is there a way to install iTunes on an external HD?

Phil