Whenever possible, look for peer-reviewed empirical research. These are articles or books written by experts in your field of interest, whose work has been read and vouched for by other experts in the same field. These can be found in scientific journals or via an online search.
Every type has a different aim. An argumentative work has to show a few sides of a particular issue and provides arguments in favor of one of them, a definition project aims to provide a clear explanation and analysis of one specific matter. Cause and effect research paper writing requires you to present a logical chain of causes and effects that relate to the selected issue, while reports simply outline a study (or studies) that were conducted previously. Interpretive papers are similar to definition ones. Compare and contrast ones, as a rule, describe the same issue from the perspectives of two different authors (scientists), while analytical research paper writing requires you to create a deep analytics of various opinions regarding the same issue.
APA format is used by researchers in the social sciences field, and requires in-text citations as well. It ends the paper with a “references” page, and may also have section headers between body paragraphs.
Any information that doesn’t fit within the framework of your outline, and doesn’t directly support your thesis statement, no matter how interesting, doesn’t belong in your research paper. Keep your focus narrow and avoid the kitchen sink approach. (You know, the one where you throw in every bit of interesting research you uncovered, including the fungal growth in the U-joint of your kitchen sink?) Everything you learn may be fascinating, but not all of it is going to be relevant to your paper.