It's like talking, but with words

Today's post is all about dialogue.  If this is an element of writing you struggle with, the Fiction Factory is here to help!
One of the best ways to learn about it is to read well written dialogue.  I would reccommend Elmore Leonard for this.  Even at his age, the man still writes whip-smart and razor-sharp dialogue.  He even slips dialogue into his narration from time to time, but this is a trick best suited to the professional.  Still, if you're ambitious, give it a shot if you want.  If you've never read his work, I'd suggest you look for a book like Pagan Babies, or The Hot Kid.  His older work is just as good, too.  You may have noticed I'm currently reading LaBrava.  This book has some dynamite exchanges between characters.  When Elmore Leonard's characters speak, it's as if real people, maybe even people you know, are speaking.  The reader has an ingrained system for detecting bad dialogue.  If the words don't sound natural, your readers will pick up on that, and thus be taken out of the story.  This is something to be avoided at all costs, so good dialogue is essential to good storytelling.  You can write a legendary story, but it will be nothing if your characters can't talk to each other without sounding strange.
A few other writers you may want to check out for dialogue:  Dean Koontz, Brad Meltzer, Stephen King, and Ed McBain.  I'm sure I've forgotten some other good ones, so that's what the comment section is for!
If you're the type to prefer real life experience, I suggest you travel to a local coffee shop or something of the sort, (don't forget to buy something first) and sit back and listen to the conversations.  It's not polite to eavesdrop on people, I know, but what you will learn can hold great benefits.
This is about all I have to say on the subject, but I will take this time to add a quick note about comic books.  In terms of writing, comics are basically pure dialogue.  Yes, there's plot and character as well, but what the reader sees boils down to dialogue.  I'm not saying that every comic book is a goldmine of brilliant writing, but when they know what they're doing, there is something worthwhile there, if you look for it.  I'd reccommend the works of Alan Moore, Gail Simone (Secret Six), or Geoff Johns for good dialogue in comics.  Incidentally, Brad Meltzer had also dabbled in comics as well.
If you have any questions, feel free to post them in the comments, and I'll try to answer them as best I can.