Magnet wire can be ordered from one of the manufacturers:
MWS Wire Industries
31200 Cedar Valley
Westlake Village, CA 91362
It comes in a wide number of gauges, and colors of the lacquer
coating - from colors they call natural(copper, golds, maroons),
to reds, greens, blues, purple, black.
One can often find partial spools in electronic surplus places,
or smaller spools at retail radio or hobby shops. It is called
magnet wire because they use it to wind the electro magnets in
motors. The lacquer coating acts as insulation and has been
formulated to be able to bend without breaking. One cannot
anneal or silver solder it however.