Hi Craig...I do not think you can use your iPad as a modem to connect to your pc. If your PC is connected to Internet with its own modem-you can access the AppStore online to your itunes than do a direct sync of your iPad to your pc using the USB cord supplied.
Or you can go to a local library or McDonald's and use their free wifi and download that way to your iPad.
Anyways...Welcome to the iPadForum! This forum is loaded with invaluable information which contain topics including: General Discussion of the iPad, iPad Operating System, iPad App Store, Accessories, and Ipad for Business and Education.
The iPadForum also includes a Regional Ipad Group for international users across the world. This is a wonderful area to "find" members from your own country. See here:Regional iPad Groups