The best overall starting point for historical intellectual property materials are on HeinOnline:
Federal Copyright Law. William Manz ed. KF2988.8
Legislative History of the 1909 Copyright Act. E. Fulton Brylawski & Abe Goldman eds. KF2989.54.A15B79
Omnibus Copyright Revision Legislative History. George S. Grossman ed. KF2988.8
Kaminstein Legislative History Project: a Compendium and Analytical Index of Materials Leading to the Copyright Act of 1976. Alan Latman & James E. Lightstone eds. (1985). KF2989.56.A16K35
Historical Foundations of the Law Relating to Trademarks. Frank I. Schechter (1925). KF3180.Sch21x