This question came up in a recent Websites 101 class. Weebly (a website that lets you build your own free website) has an easy-to-use interface that lets you build a store quickly and efficiently. It allows just about any shipping company you like, and it gives your customers several popular payment options (including PayPal, credit cards, etc.).
You can build a link on your web page that points to a Weebly storefront. On the Weebly storefront you can add all your items and pricing information, and then provide a return link from the storefront back to your web page.
However, the Weebly storefront will probably not match the look and feel of your web page. Branding is a vitally important part of any website. You can try to match the colors and fonts of your existing website on the Weebly page, and even use your own graphics and logos, but it’s still not going to look exactly like your current site.
My question is, why use a Weebly storefront page when there are so many e-commerce tools available that “plug-and-play” directly into your existing website and copy your look and feel exactly? Here are a few examples: