Official Sites
United States Patent & Trademark Office (USPTO)
Patent & Trademark Depository Library Association (PTDLA)
U.S. Code Title 35 - Patents
Peer to Patent


Additional Search Tools
Pat 2 PDF great site for viewing and printing patents in PDF format
U.S. Patent Number Guide
Google Patents
Free Patents Online


Classification Search Tutorials
Audio Visual Tutorial Please turn on your speakers
Text Tutorial Read through the steps as you search the USPTO website yourself in an adjoining screen


Other Sites of Interest
Patent Librarian's Notebook
Patent Law Resources