Iphone

iPhone 3G: 

Press Settings icon from the SpringBoard of your iPhone. Scroll down to General Menu
   


Press Network Menu.
On the "Network" screen there is a choice Enable 3G. You don´t need to change this setting.
And if you don´t have an iPhone 3G, this choice is not available. Press Cellular Data Network.
   


Under APN field, enter "internet" as the APN
Then go back to the Network menu by pressing Network button at top left
 


If you want to use Data Roaming at this time, press Data Roaming to turn it on.  Press Network button at top left (left screen shot) then turn Data Roaming on.
 
Now you have Setup Edge/GPRS on your iPhone and ready to surf the internet.