E-Mail is a Primary source of information if the Sender of the E-mail is the subject of the Research, contains unedited visual or auditory contents which are needed for your research and directly link to the research Subject in question.
If the Sender witnessed an event, conversation etc, then relays the information gathered i.e. observed without providing any type of direct source to that information, such as the link, recording, original unedited copy, etc. the E-Mail is at beat a secondary source of information.
News group follows the same set of rules. Anything you did not witness yourself or receive direct unquestionable evidence to support your research is at best a secondary source. Anything you witnessed directly which was observed in the presence of the News Group either in person or through digital medium, but then lack the physical, visual, or auditory evidence to support your research Makes you the secondary source.
FAQ not answered directly by the Entity, Spox person representing the subject at which your question is aimed becomes at best the tertiary source and anything past secondary is hearsay or gossip. As you become the 4th even with Visual Or Auditory. If using FAQ's you either need a certified individual which directly represents the subject of your question. i.e. "How to I build a Dell Computer?" only a certified Dell Technician, Patent Holder, or basically anyone having the Direct knowledge of how to complete this task, can verifiably answer that question. Anyone who has built a computer in general is considered a secondary source and therefore cannot tell you how to build a dell computer. They may also be used to prove that people are indeed interested, statistically, in a specific topic.
That is all I have and some of it may be incorrect. I can only afford the content provided with the understanding that my knowledge is limited to only what I understand about Using digital and Intimate sources for a blog.