This is post is now quite old and the the information it contains may be out of date or innacurate.
osCommerce is undoubtedly the most popular open source ecommerce system available today. It has been around for a long time and whilst this does mean that it is not particularly cutting edge in the way it is put together, it also means that it is tried and tested and guaranteed to work well.
One of the other great things about osCommerce is the fact that it has also spawned various offshoots or forks. Most notably these include Zen Cart and CRELoaded. There are a few other less well know osCommerce offshoots as well. These are basically packages that have taken the base osCommerce system and added a selection of customisations and extra features to make it a more complete package.
My particular preference is the CRELoaded version of osCommerce. This version includes an excellent templating system making it very easy to get the store to look exactly how you want with minimal fuss. It also includes some excellent catalogue management tools including the incredibly useful and powerful easypopulate system. This system allows you to edit your products via spreadsheet. With a little modification it can handle bulk insertions of tens or even hundreds of thousands of products.
Edmonds Commerce are a freelance PHP development specialist and have years of experience with all flavours of osCommerce. If you have any customisation, optimisation or SEO requirements for your existing osCommerce store, or if you are looking to set up a new ecommerce site based around osCommerce – Simply get in touch.