How do I cite business sources in APA format?

Steve's guide to APA style is excellent

This is a very common question, and rather than reinvent the wheel, I suggest visiting Steve Kramer’ guide to Citing Business Databases in APA format.  Steve covers many of the databases that we use and provides examples for citations in APA format.  For those databases that we have that are not covered in the guide, you should be able to borrow from other examples and adapt those to your needs.  The import thing is to be consistent and to provide as much information as possible, thereby making it easier for others to follow your research trail.