Discussions of existing products and services are most often found in business specific journals and magazine. These three tools can help you find this material.
You can focus your search to trade journals, industry reports, market reports, SWOT analyses, and more, by using filtering options in these two management/business databases:
After you have run your keyword search:
Here is an example of that menu from Business Source Complete.
To see all of your options here, click on the 'show more' link.