United States Patent and Trademark Office

USPTO Home Page - http://www.uspto.gov/
USPTO Patents - http://www.uspto.gov/main/patents.htm
USPTO Patent Search - http://patft.uspto.gov/netahtml/PTO/srchnum.htm
USPTO Trademarks - http://www.uspto.gov/main/trademarks.htm
USPTO Manual of Patent Examining Procedure - http://www.uspto.gov/web/offices/pac/mpep/mpep.htm

International

World Intellectual Property Organization (WIPO) - http://www.wipo.int/portal/index.html.en
Patent Cooperation Treaty (PCT) Office of USPTO - http://www.uspto.gov/web/offices/pac/dapps/pct/
European Patent Office - http://www.epo.co.at/index.en.php
Japanese Patent Office - http://www.jpo.go.jp/

IP Associations and Resources

National Association of Patent Practitioners (NAPP) - http://www.napp.org/
American Intellectual Property Law Association - http://www.aipla.org/
International Intellectual Property Alliance - http://www.iipa.com/

Patent Search and Ordering Resources
Free Patents Online - http://www.freepatentsonline.com/
Patents to PDF - http://www.pat2pdf.org/

Law Associations

American Bar Association - http://www.abanet.org/
State Bar of California - http://www.calbar.ca.gov/state/calbar/calbar_home.jsp