If you are traveling with a laptop, be sure to check out this list of free wireless hotspots from wififreespot.com.
HotspotHaven.com has a wireless hotspot search engine to find free and paid wireless access around the world.
Wi-fihotspotlist.com can help you find commercial wireless Internet access.
Wifinder.com has a list of commercial hotspots.
Jwire.com also has an extensive list of commercial and free wireless Internet hotspots.