The module is in two places, how you move it has two ways.
Look in the top right and you should see it. Click once on it, then scroll slowly down, looking on the right - you will see a stack that represents your page modules. The one you just added will be at the bottom. Using this small stack you can drag the module up to where you want it to be on your page. Then press the REORDER button under the stack.
If you want it to only be half width, then double click the amazon module in the stack and it goes to half size. Now drag it up the list and when you let go you'll see it lies over another module... that is the module it would sit inside.
The other way to move the module is on the page itself. Once you've clicked the module on the top right, if you scroll to the bottom of your page you'll see it there. You can use the green arrows at the top of the module to move it up one place at a time... this is more long-winded though than drag/dropping it within the small stack that's on the right.
I hope that was clear :)