Hi Jennifer,
I wrote several corporate histories in the last few years.  The best was
one on Lincoln National Corporation, at the behest of the CEO; it was
titled "90 Years and Growing," so it wasn't exactly an anniversary, but
the CEO wanted a history before he left the company.  Another I wrote
was an anniversary piece, on the HWI Hardware cooperative (it's 50th
anniversary; I did this in conjunction with the initial work of the
newly retired CEO -- a common thing).  So, too, was my work on the Rea
Magnet Wire Company, initially undertaken by the former CEO, then by a
writer I suggested upon my leaving that community (to come here to
Alaska) and then having to rewrite the work as a ghost writer.  I've
also written smaller pieces on a savings and loan, and unpublished
manuscript on a foundation and its family, and a church (as an
"assistant writer," which is another guise of what you seem to want to
do).
  Do you have specific questions about this buz?  Happy to answer as
best I can.
Mike