For Bluetooth, you will need either an access point (at work or at home) or a BT card for the PDA and a BT enabled cell phone. I've used AT&T and T-Mobile for data. AT&T is a bit faster, but T-Mobile has a better plan ($20 for all you can eat GPRS). You can check out the BT access points and cards here: http://www.pdabuyersguide.com/tips/bluetooth.htm
For Wifi, you will need a wifi card for your X5. Here are some wifi cards you can check out: http://www.pdabuyersguide.com/tips/wifi.htm Once you X5 has wifi, you can use many access points and hotspots around the country, some are free, others you pay a fee as you go.