The names are so similar that Cottonwood Quilts may be able to prevent you from using Cottonwood Creek Quilts.
Because this is an online store, I'd start with the domain name. You want something that is short, easy to remember and won't be plagued with spelling errors. To check domain names, go to one of the registrars (godaddy.com for example) and see if the name is available. Once you see it is available, go ahead and register it before someone else does. You should try and do that before you post the name here, so no one else grabs it. It's only about $10 to register the name.
After that I would check with your state database and see if there are any conflicts.