Coded targets are created using the File->Create Coded Targets menu option. They can be created as either a post script (.ps) file or directly on a printer.
Non-coded targets can be any high contrast circular dot. These could be created using a printer, a hole punch, a stencil or any process that produces circles.
www.retrotargets.com with the "E" series targets.
www.brunson.us/p/ListInvar.asp
Also many sign shops can supply white or black 3M retro-reflective sign material and cut circular targets out of it. For retro-reflective coded targets an advanced and well equipped sign shop may be able do them if they can accept pdf or postscript files.