Most FAQ databases that you might find pertains to a specific hosting criteria (functionality) or is too Generalized. For eg, if you are providing hosting with, let's say Virtualmin or Kloxo control panel, a KB with cPanel related FAQ's would be impractical.
I feel that it's better off creating your own database then getting it from somewhere else, since FAQ's about, suppose sales, may be applicable for your company. It doesn't hurt though to refer an already created FAQ
