ifconfig on the zaurus will show you the current network interfaces and their config.
ipconfig /all does the same on xp.
If you want to see the zaurus in Network Places (or whatever MS is calling it this version) then you will need to start samba on the Z. Currently samba is only started automatically when you connect the Z to pc via usb cable.
Odd that sharp should decide to only allow samba over usb and not to recognise usb as a network in qtopia by default.
Samba can be started via
(may be qtsamba - sorry don't have the Z handy to check) You could add that to one of the network up scripts to have it done automatically