The Starrett adhesive measuring tapes are available online from Enco
http://www.use-enco.com/CGI/INLMK3?PMK0NO=374006 in 4, 6, or 12 ft.
lengths.

Oregon Rule Co., which another poster recommended, has longer tapes. A
former employer of mine got a 30 ft. tape from them.

--
-- Steve