The research paper can be one of two things. It can be an exercise prescribed by professors so that students get to experience various texts, or it can be a paper written for the sake of showing important information.
What kind of class are you taking? Depending on the class, you might need one kind of research paper or another.
Here is some helpful advice: When you have to write a research paper and use a lot of books/articles (i.e. "sources"), think of your paper as alchemy. You mix these five or ten articles together, and you infuse it with your own ideas... and the paper is created.
For the kind of research paper that involves researching a particular subject and using a lot of sources, it is easy: just write about what the other people have said. (And don't forget to cite the source). Then, draw your own conclusion.
A research paper is generally exactly what you would expect it to be, a paper that summarizes and evaluates the research available on a given topic. So, you would start by reading all the material you can find on the topic you are researching. If the topic isn't particularly controversial, then you are merely collecting and organizing facts. If you were writing about the life cycle of the piranha, for instance, you would simply have to read several sources that described the fish and then write up what you had learned in your own words, with some citations thrown in to back up your points. If the topic is controversial, though, you would have to do a bit more work. If you were writing about the effectiveness of gun control laws, for instance, you would cite research backing up various points of view, then evaluate the research to come to your own conclusion about how effective gun control was at reducing crime. This might involve looking at who funded various studies, what methodology they used, how they defined crime, what sorts of gun control they analyzed, what sort of control, if any, was present, etc.
