I think your real question here is not about the format of a bibliography but about the requirements for citation in various kinds of work.
Some fields have very specific requirements both for what you are supposed to cite and for how you are supposed to cite it. These are laid out in style guides and different fields have different style guides that they use. If you are writing in a field that has such a style guide or for a journal or publisher that requires you conform to such a style guide, you need to buy the appropriate guide and use it.
Outside of that, you need to think about the functions of citations. Citations exist for two reasons:
To establish the authority of a claim. How often you need to do this depends on how much trust your audience places in you.
To enable the reader to find additional information on a point if they need it.
In academic writing there is a general requirement that you prove the authority of every significant claim that you make. Basically, you proceed on the basis that there is zero trust in anything you say and you have to support everything. In this case, you have to keep track of the source of every claim you make and cite it according to the prevailing style guide.
In professional writing, you will enjoy a degree of trust based on your qualifications and most readers will not require that you prove every claim you make as long as it is not controversial or contrary to received wisdom. In this case, you cite judiciously to back up any claims that people might question or to give people access to further information if they need it.
In popular writing, you are generally assumed to deserve a high degree of trust and readers are presumed to be willing to take you at your word. Publishers may want you to prove you are qualified to write about the subject, but you will rarely be required to formally cite any sources, though you may do so informally in the text itself as a means of emphasis. (As in, "according to the CIA ...")
It is worth noting, however, that there is a genre of popular writing typified by Malcolm Gladwell, which involves the rather breathless boosting and popularization of soft scientific research. In this case, the text tends to tell the story of the research rather than citing the results the way an academic paper might. These books tend to have extensive bibliographies, though not usually a formal citation system.
All that said, there is no general answer. In the end you need to talk to your publisher about the level and style of citation they will want you to provide, and until you know that, you would be well advised to meticulously note all your sources. There is nothing more tedious that trying to track down the source of something after the fact.