Hey I wanna a porteur rack, where can I get some aluminum tubing?

Brakeless with a front rack - very NYC!

Looks very neatly done. Personally I'd use chromoly for something like that cos I think it will be a fair bit stronger. Keep an eye on the rivet holes as the rivets might start to enlarge them once you combine grit from the roads with vibration and bumps.
possibly not brakeless.....look again