I recommend Robert Gellerman's "The American Reed Organ and the
Harmonium" ISBN: 1879511126, for general reed organ & restoration info.
You can get it directly from the author, who can be contacted at:
Gellermanf@aol.com

An excellent resource for info on Estey Organs is Robert Whiting's
"Estey Reed Organs on Parade" which is available from: Out-Back
Mechanical Music, 6 Front Street, Bainbridge, New York 13733

Some useful reed organ web sites:

The Reed Organ Home Page:
    http://cs.bluffton.edu/~estell/organs/

New Englsnd Organ Works:
    http://www.reston.com/OrganWorks/OrganWorks.html

Good luck,

Bob Godfried
Bronx, NYC NY