SAP E-Commerce (or) ISA is a web shop that allows you to sell specified products in the World Wide Web and control certain sales transactions within both Business-to-Consumer and Business-to-Business Internet Sales. It comes with B2B and B2C scenarios. In technical terms it’s a J2EE based application developed using STRUTS framework. You can deploy this application on SAP J2ee Server (Example: SAP Portal). ISA runs on top of SAP ECC or SAP CRM.

In my experience standard ISA does not provide rich look & feel and not end user friendly. SAP allows doing customization using NWDI (NetWeaver Development Infrastructure). Below are some of the helpful resource which makes your job easier when you are developing or extending standard ISA code.

12 things about E-Commerce (I wish someone would have told me)

Extending ISA (or) E-Commerce Step By Step Vedio Tutorials

How To Call Function Module in E-Commerce

Example Shops:

https://shop.lonza.com/shop/b2c/start/(xcm=lonza_b2b)/.do

http://www.futurebazaar.com/indexFutureBazaar.jsp