Leigh Gibbs just emailed in about this officialcharts.com website where you can find pretty much every number 1 tune since 1952 ! Leigh says…
… this site has 30 secs of every number 1 ever made and they are all in WMA format. So they’re already “made to fit” Window Mobile. All you need to do is click the track you want to listen to, then right click “Save as” on the tune and you have your ringtone!”