wow, he bought a Clie and gave you his Axim X5? That's crazy. I'd never trade my X5 for a Clie! You got a crazy good deal. :D
As for your question, you need to install Microsoft ActiveSync. I assume he gave you the sync cable/cradle along with it? Go here to download ActiveSync from Microsoft (it's free) :
http://www.microsoft.com/windowsmobi...ivesync37.mspx
--nomad