Forced Dialog

Self-Editing for Fiction Writers by Sol Stein.

As for forced dialogue -- Writing Dialogue by Tom Chiarella really helped me understand the art of "authentic" dialogue-writing. Also, go to a busy place (coffee shop, bus station, etc.) and listen to real people talk. Real dialogue does not "dole" out information as if someone is manipulating it. Real dialogue is organic, natural, and not necessarily direct. Read Chiarella's book and you may get some good insights.

Make sure the dialogue suits the character.

Balance between 'natural' and 'dialogueish' - meaning, there will be some 'umms,coughs, pauses, etc, but the overall conversation should make fairly rapid progress to it's conclusion.

Find the balance between writing how people really speak and cutting out all (most) of the mindless crap that doesn't move the story forward.

And in addition to the book that Ray advocated, there is "Dialogue" by Gloria Kempton and "Lessons From a Lifetime of Writing" by David Morrell. Both are good.

ETA: Sorry, those books are not about editing--but they're still good, so I'll leave them in the post.

Make sure you also have a story (as opposed to just an idea). Forced dialogue can develop if the story's too thin, and there's nothing for the character to do.

Make sure what people are saying is an actual conversation and not just info dumping through dialog. Would people in this situation really say these things? Would this character say these things in this way?

Also, read it out loud. You'll hear forced dialog a lot easier that way.