I found this in a few different places around the 'net - hopefully it's helpful:
Save Time and Effort in Typing URL Addresses
With Internet Explorer 6 in Windows XP, typing Web addresses can be a breeze.
- Type the domain of an address, such as Microsoft, and then press Ctrl+ENTER. Internet Explorer automatically wraps "http://www....com" around what you typed.
- Not sure if the site uses a .com extension? Just type the domain of the address, and then press ENTER. Internet Explorer tries to find the site by using the various extensions.
- If you need to edit an address, you can use Ctrl+LEFT ARROW and Ctrl+RIGHT ARROW to easily move between different parts of the address separated by periods.