Selecting an author to write a research paper on, I would suggest two criteria, which echo the posts above:
- choose an author whose work you enjoy
- choose an author who has been written about, critically and popularly
There are many, many writers out there who are the subject of extensive study and whose work is the subject of study: William Faulkner, Zora Neale Hurston, James Baldwin, Virginia Woolf...
The best way to narrow your choices is to find out who you really want to know about. Find someone that interests you.
If I had to choose an author to do a research paper on today, I'd choose Fyodor Dostoyevky. Partly because I happen to be reading one of his books right now and partly because his personal life seems to have seeped into his fiction. I'd like to know how much this is the case, how much is the man represented/present in the fiction.