Avoid using many long, direct quotes. Although your paper is based on research, the point is for you to present your own ideas. Unless the quote you intend on using is absolutely necessary, try paraphrasing and analyzing it in your own words instead.
An argumentative research paper takes a position on a contentious issue and argues for one point of view. The issue should be debatable with a logical counter argument.
A research paper is an expanded essay that presents your own interpretation or evaluation or argument. When you write an essay, you use everything that you personally know and have thought about a subject. When you write a research paper you build upon what you know about the subject and make a deliberate attempt to find out what experts know. A research paper involves surveying a field of knowledge in order to find the best possible information in that field. And that survey can be orderly and focused, if you know how to approach it. Do not worry--you would not get lost in a sea of sources.
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.