Def don't use Godaddy their hosting is pretty poor, they are very expensive and the website builder very limiting.
Learn how to build your own site through
http://www.w3schools.com/website/default.asp - honestly you will get a basic understanding of how it works in an afternoon. All you need to know for a decent website is on that site.
Once you have your site built on your pc and tested, you can register your domain and look for hosting. I use fasthost as they are ok price wise and have a lot of tools available. You then just migrate the files on to your public directory on your host and you are live.
edit re shopping cart - you can probably buy some sort of package to add to your site, but the first thing you would need would be a payment processor, they might have software that includes the shopping cart and all you would need to do would be add a button on the relevant pages.