Not sure what you want to edit with a "website builder".
If you mean edit cube carts basic pages and simply add info. Then you can edit pages and items via the admin back end.
If you mean edit the way it looks, ie templates. As far as I know theres no *easy* way to edit it. You have to know html/xhtml/css to edit the templates of cube cart and any other shopping cart that I know of.
If you are asking for a website seperate from the shopping cart, then there are "website builders" but as I have no use for them I do not know of any. WYSIWYG editors are another option but they require a little more knowledge and they generally produce poor coding.
Sorry if that dosen't help.
