I made a quickie DSLR shoulder mount for my Canon 5D this weekend from some old pipe and an Ikea cutting board. It is a great little starter rig!
more pictures here: http://www.flickr.com/photos/kimncris/sets/72157625818219691/with/5409970068/
I've already added a tripod mount and cable release since the video was made...
a good source for aluminum
more info here