I have been teaching for some time, always including art history and artists in my lesson plans. I have not had Internet access most of my career, and have only used the visuals that come with textbook adoption, posters from museums,and calendars.
Then recently, I attended a Graduate course in contemporary (artists are still living) art history and it blew me away! There were so many good contemporary artists that I was on fire to share them with my students. What I discovered was that 1) there are not many resources out there for using contemporary art in elementary art classrooms, and 2) much of the art is so conceptual that it is hard to use on an elementary level. (Well, and 3) lot of nudity and inappropriate content!)
One thing that did work for me is the number of artists using recycled materials (like Tara Donovan) and objects from nature (think Andy Goldsworthy).
I'd like to move my art classes into the 21st century, but here are the "Givens": I still only have 40-45 minutes once-a-week with each class, I teach in an urban school, so not a lot of $ for supplies, and, of course, I still have to correlate with core academics (math, reading, science), no computer access--for students--in the art class, although I can sign up to use the "flex lab" and take a class there once in a while if I plan ahead.