The Best SFF Con?

I'd have to say Worldcon is probably the best. It draws people from all over the world. But I do have fun memories of Contact, the Evansville Indiana convention the year First Fandom came. I've never forgotten meeting Ackerman and Moskowitz.

I imagine Worldcon is what you're after.

If you do Fantasy, then World Fantasy would be what you're looking for. It's much more a writer's con than WorldCon, which is more fan-oriented to my experience.

I adore World Cons, and the first one I ever went to was a World Con, but for your first con, you want something smaller--you don't want to be a total newbie, you want to already have some people you know.

I'd suggest World Fantasy, or Wiscon, or Boskone for a very first. If you can make it, I'd love love love to go to fourth St.

Keep in mind that cons are for fans -- agents and editors etc. are there part/primarily there because they're fans too.

And read what TNH says about con attending.

Is Boskone where they give the Compton Crook Award? That's a nice little con, whichever con that is.

We get a lot of SF/F authors at our local con (ConFluence--Pittsburgh, July), but not many editors or agents, but it is a good networking con.

For contact with editors/agents/pros then you can't beat the two Worldcons: World Fantasy and World SF.
For improving your writing, many of the smaller cons run a workshop with a guest pro teaching. A friend of mine ran the ArmadilloCon workshop and they had Sharyn November as guest pro last year.

I'm at BEA. I got a free copy of The Graveyard Book signed by the man in the leather jacket himself.

Then, I met John Scalzi at the Wizards of the Coast Book. Then I met Kelly link and Gavin J. Grant.

Also, nearly all the books are free.

Compton Crook is Balticon.

Besides the Worldcon/World Fantasy Con, shows where you can meet the most pros? I'd have to put in my bid on Dragon*Con in Atlanta. But, it is a multi-media convention, with almost 35,000 attending every year not counting almost 1000 guests from TV, movies, literature, comics, anime, professional costumers, game designers and musicians.

It's a swirling maelstrom the first time you get swept into it, but as a writer, I've been able to go from a conversation with the chief engineer of the "space elevator" project, to sitting and listening to Chris Claremont talking about his latest comic project to discussing military tactics with Jerry Pournelle to sharing a bottle of scotch with Jason Carter of Bab5 fame or getting a quick sketch from Don Rosa of Disney comic fame.

It's different than your regular convention also because it's a 4-day, 24-hour con, but the writer's track is pretty well run with new authors and old pros sharing the stage. Our own Ann Crispin also runs a beginner's and an advanced writer's track there. Those slots tend to sell out fast.

(I like it because they have their own Star Trek track which dedicates several panels to the writers (both screen writers and tie-in authors) as well as the TV personalities.)