Brian Goldberg writes from New York Comic Con for Bleeding Cool:
I recently started a sketch book. My previous collection of sketches were loose and all over the place. If you're a sketch collector of art done by professional comic artists, New York Comic Con is a great place to add to your collection. Artist Alley is the perfect setting to meet and greet the heroes behind the super heroes. Timing is everything with sketch collecting. An artist might be busy and not have the time when you hit their booth. If you go to an in-booth signing, it's best to go early. Comic artists get tired just like everyone else.
Be okay with head sketches. Artists only have some much time and a lot on their plate. If you want a full figure drawing, expect to pay a premium.
I also think it's a great idea to ask for a sketch of a character than an artist is comfortable drawing and in a style they are comfortable drawing in. For example, I would ask Ryan Stegman to draw Medusa, Scarlet Spider, or Wolverine and not Galactus.
The sketches I was able to get this con were:
Hulking by Jim Cheung
Hannah from Rat Queens by Roc Upchurch
Olive Silverlock by Karl Kerschl
Spider Gwen by Robbi Rodriguez
Savage Dragon by Erik Larsen
Quicksilver in All New X-Factor style by Kris Anka
Rocket Raccoon by Sara Pichelli
Warpath by Franco
Gathering these gems took some effort on my part. My work and especially the artists' work definitely paid off.
And here's a gallery of those sketches: