So you setup your osCommerce store and adjusted the settings for your new store. osCommerce by default will allow you to have a functioning online store with the ability to sell items and ship them.
I would say though, that 99% of new users will want added functions that do not come with osCommerce by default. Some additional mods or contributions that can help make your store more successful include Ultimate SEO URLs, which will give you more descriptive urls for products,categories,manufacturers, etc. This will also improve your listings in search engines.
By default, osCommerce comes with many checkout options including PayPal, Authorize.net,etc. So if you just started out and don’t have strong traffic and sales, you can also integrate Google Checkout into your osCommerce store. This way you do not have to pay monthly fees to a service prodvider such as Authorize.net or CCBill.
Do you have many products to list in your osCommerce store and don’t want to list them individually. A good option would be Easy Populate. Easy Populate will also you to edit any csv file and then upload hundreds or thousands products at one time. This is great if you have a supplier or dropshipper that allows you to download a products files with many products. Using Excel or anytype of spreadsheet software you can easily edit your products in a matter of minutes and upload them.
Finally, another good contribution is the Super Tracker Mod which will allows you to track referring page
referring query (so we can get at keywords used if search engine)
landing page (including query string – important for Pay Per Click campaign assessment)
arrival time
exit time
exit page
IP address
country code / country name
customer’s cart contents
Number of clicks on the site (accuracy is not 100% as this is recorded based on session ID)
Categories Viewed
Products viewed
Customer ID (if signed in)
Order ID (if order was placed)
Were products added to cart (true/false)
Did the customer Checkout (true/false). This is a great mod or contribution which will allow you to access the traffic coming to your online store.
There are many more mods and contributions at the osCommerce Website.
You may also wish to checkout the Addtional Addons available. The chances are very good you will find a mod that will do what you want your online store to do.