Web Applications > E-commerce: What is the best platform for a small ecommerce enabled website?

You're in great shape as far as knowing what you want and understanding the e-commerce landscape - that's a good head-start in finding a solution. I assume by "off-site fullfilment" you mean a hosted service, where your customers leave your site to either shop or complete the purchase process. Hosted options don't necessarily mean leaving your site . . . if your entire site is hosted with that e-commerce hosting provider. But that option tends to be either restrictive in design and non-ecommerce functionality or quite expensive.

So other option is to host you're own database e-commerce application and integrate it into your site design. Of course, ongoing IT support will be needed when going this route, but some applications are more stable than others.

* I saw a recommendation for osCommerce in another answer---but I couldn't disagree more (personally). In an article I wrote about e-commerce set-up and considerations (link below), I touch on the ills of osCommerce.

* I also saw the recommendation for Magento and have a few comments. First, Magento is a beautiful, well thought out application. The back-end look & feel and usability is on par with the best web programs out there. From my early experience with it though, I have found the front end customization to be more difficult than my recommendation below. When looking to use it for a project, I found several features (I don't recall which - perhaps internet gateway integration) to be limited. Also, being a new product to the market, I didn't feel that all the bugs had been worked out yet and read some posts in their forum that sent up a red flag for me.

MY RECOMMENDATION
* Per integration, it's helps to know whether you already have a site or a specific design that you're interested in. Customizing shopping carts can be difficult/costly. I use Ecommerce Templates (link below), which fully sinks into your existing or desired site design (client site example link below). While this is an incredibly versatile and stable platform, it does not have the pretty back-end of a Wordpress application. It's stability is incredible though---after setting clients up and making any needed post-launch tweaks, I have stretches of a year or more without being called in for support.

SUGGESTIONS
I would suggest listing the absolute necessities that you have and then looking around with those criteria. Even my suggestion may not have the functionality that you need. Following are some functional criteria that can influence which application you need.
- physical vs. virtual product
- shipping options (vendors, pick up, multiple origins)
- internet gateway (i.e. Authorize.net is common, but BofA is obscure)
- inventory management (Quickbooks POS integration is rare)
- social community features (product rating, comments)

Hope this helped.
Links:

* http://appliedwebvitals.com/blog/7/setting-up-e-commerce-steps-consideratio...
* http://www.ecommercetemplates.com/
* http://theteakhut.com/