I'm in an online Greeting Card Association group through Yahoo, and another member posted a cool link to a new product soon to be released by Wacom. This Inkling video shows how you can turn your ballpoint sketchpad drawings into digital images like magic using the Wacom Inkling Digital Sketch Pen.
For now, though, I'm still doing my sketches on my PC. I recently found a way to put borders around my cartoon pieces. I watched this video that explains how to create stencils using the 'linked offset' in Inkscape (by Aussie Carolyn) a few days ago, and then I realized that I could use this technique for adding dark outlines to my cartoons, as shown in yesterday's 365-Day Challenge project (day 48, the owl in the tree) and the card that later got approved using the same image (left).
Finally, in the Greeting Card group I mentioned above, that same member also provided us with a link to an online photography magazine called PhotographyBB. Since I'm not much of a photographer, I don't usually spend much time with these kinds of resources, but this one seems very useful for explaining digital illustrating techniques as well. In the Aug. 2011 issue, (beginning on page 44) a technique to turn photographs into pencil sketches with Photoshop is explained. I don't have Photoshop yet, but I do have Gimp, and when I'm more comfortable using it, I will try out this technique for one of my daily challenge projects. :)