The word "robotics" can mean many things - and so can "art". To some, robotics is about factory-automation systems - giant robotic welding arms and such. To others, including most "hobbyists", a robot is autonomous and mobile, with wheels or legs, eyes or obstacle detectors, a gripper, and an on-board control and navigation system. At ARG, we use it in a much more general sense, which escapes easy definition - as does "art". It can include everything from simple motorized sculptures to complex computer-controlled environments.
One of the best ways to learn about art and robotics is to see what some actual people have actually done, and what people have said about it. You can also find out about relevant schools, organizations, and festivals, and you can add your own links to this section:
How? If you want to work with technology, there's a lot to learn. The good news is that you can do great stuff with simple means. Never underestimate simplicity and elegance in art - the bleeding-edge is no substitute for thoughtfulness, and more often than not produces work that is just clever cliché. With that in mind though, there is a wealth of technical information available on this site, elsewhere on the web and other media, and through personal contacts: