So you don't have the one with 3G from what I gather?
If I have understood correctly, there are two ways of doing it - by using your wireless connection or by connecting it to the computer. I think the wireless one is easiest.
1. Wireless. You don't need the 3G option on your kindle to transfer files wirelessly as long as you are somewhere where you can connect to the internet wirelessly - presumably at your home. Purchase the books as per usual. Switch on your kindle and make sure the wireless is switched on (Menu - turn wireless on). Then press HOME button and MENU again. One of the options you will have is 'sync and check for items' - choose this and the books you purchased on Amazon should appear on your list (they may take a few seconds - be patient).
2. If you do not have a wireless connection, plug your kindle in to your computer using the USB connection. On the Amazon website, go to the 'manage my kindle section'. There should be a menu on the left with 'your kindle library'. Here you will see a list of things you have bought. Next to each will be an 'Action' button. If you click on the arrow to the side of the action button, there is an option to 'download and transfer.'
Hope this makes sense - it's a bit difficult to explain like this.
There is more help here:
Kahlan My swaps Had an accident?
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