I just found a source for precut plexiglass shapes. I was actually looking for templates for an airplane block and since I couldn't find any, looked for custom made. I found this online shop that does laser-cut plexiglass templates, and they will make my template set very reasonably (it should be shipped tomorrow). I also see on their site that they sell block template sets, nested sets of shapes in 1/4" and 1/8" thick, and a 4" x 18" 1/4" thick ruler. I especially like that the marks are laser engraved so they will never come off. NAYY
http://www.deepbluetemplates.com/