Wireless connection for D600

Hi,

I'm a new user with a Latitude D600.  I do not know how to use the computer with a wireless connection.   I am using MSN dial up to get to the internet.  I was in a coffee shop yesterday and could not get the wireless connection to work (others were successful).  I checked Control Panel/Network and Internet Connections/Internet Connections/Wireless Internet Connections and found:  "Enabled.  Intel (R) Wireless LAN 2100 3A Mini PCI Adapter".   Can anyone help me out?

Spencer