Writers have excellent online and professional organization resources (including libraries!) for researching the publishing business, but two topics a lot of writers don’t think about, until it’s too late:
1) Publishing scams (see, e.g. Writers Beware, from the Science Fiction and Fantasy Writers of America, Inc.)
2) What to do if your publisher goes bankrupt?
As with all legal issues, after-the-fact fixes are often trickier, more expensive, and more limited than front-end preparation, e.g. reading books and magazines that discuss legal issues in the writing and publishing world — and consulting an attorney before signing on the dotted line.
So, do your homework, talk to other writers, scour the web and the library shelves, and talk to a lawyer who knows about the publishing world.