I only recently stumbled across Muddy Colors, a group-blog written by some leading figures in the science-fiction and fantasy (SFF) genres, one illustration field where representational art (even if the subject is non-existent) still rules. It's a highly worthwhile blog, so I immediately added it to my Links list on the sidebar.
I'm not fully "into" art created by computer programs such as Adobe Photoshop or Corel Painter, so I appreciate the fact that the Muddy Colors crew use traditional handwork media as much as possible for their illustrations. Moreover, they have a keen sense of historical representational art and classical illustration which informs their professional efforts.
Blog subjects include multiple views of works as they progress from thumbnail sketch to final art, tips regarding techniques, insider views of the business side of illustration, occasional interviews with artists not part of the group, news of upcoming events such as conventions and master-classes, and even something called Crit-Submit whereby aspiring illustrators send in works to be evaluated and (often) digitally modified or corrected by a group member.
Go to the blog for a full list of contributors on the sidebar. I'll mention four of them here and toss in a few images for good measure. The instigator of Muddy Colors is Dan Dos Santos an articulate art-book junkie who specializes in book cover art. Donato Giancola (who professionally goes by the name "Donato"), considered a leader in the field despite the fact that he must deal with the consequences of an eye injury "which destroyed the macular region of my right eye (the part that lets you see detail, and yes it was permanently destroyed)." Greg Manchess who does not restrict himself to SFF. He painted a mural for the Abraham Lincoln Presidential Library in Illinois, created images for postage stamps and did illustrations for publications such as National Geographic. Arnie Fenner, who along with his wife Cathy, created and continued Spectrum, an annual publication featuring jury-selected SFF art.