It seems like Humberto Ramos has always been a big deal. I'll always remember him as playing penciler to Mark Waid in Impulse in the mid-Nineties. While Waid and Mark Wieringo created Bart Allen, it was Humberto that gave him the bigger hair and boots. He's moved on from there . . . being the only guy at Wildstorm's "Cliffhanger" imprint to have a work ethic (on Crimson and Out There) and eventually finding him way to regular work with Marvel (Amazing Spider-Man, Extraordinary X-Men). Between the fans he attracts at conventions and the prices he commands for commissions, I would consider myself fortunate to have three quick sketches from him.
However, I have managed to get more from him. When I went to Wizard World Philadelphia in 2007, I was looking for my first Doctor Who-themed sketch. I had a copy of Doctor Who Magazine with me, and I pointed Humberto out to David Tennant. Lucky for me that I had the reference, because he never saw the show. What I ended up with is something that I use as an avatar on message boards. I don't remember how much I paid for the commission, but it was worth it.
Four years later, I was in Philadelphia for what would be my last Wizard World there. When I saw Humberto on the guest list, I knew that I had to try and get something from him. I only had enough for a black-and-white bust shot, but he did Delphyne Gorgon from The Incredible Hercules amazingly well.
HONORABLE MENTIONS: Scott Ramsoomair (two sketches from the VG Cats creator, including the first Death Note-themed drawing I got), Khary Randolph (one; a city-based "concept" work of Poison Ivy), Tom Raney (eleven; five based on Outsiders), Erik Reichenbach (a self-portrait of the original ice cream guy from Survivor), Rod Reis (one watercolored shot of the "New 52" Catman on Secret Six #1), Sara Richard (four; including this commission of Sarah Jane Smith from Doctor Who that has gotten over 4,000 views on my Flickr account), Alex Robinson (six; including this sketch of Hygena from Who Wants To Be A Superhero? that got a comment on Flickr from the actual Hygena), Bill Roseman (what might be the worst sketch I've ever gotten, though I say that with love), Duncan Rouleau (three; featuring the first sketch I received at a convention), Andy Runton (a "concept" sketch from the Owly creator), Dave Ryan (three sketches, including one I wound up getting via mail).