AirlineNumbers.com
Toll free numbers of domestic and international carriers operating out of the USA.
http://www.airlinenumbers.com/

Airlines
Toll-free numbers of airlines with operations in the United States.
http://airlinetickets.flyaow.com/tollfree.htm

AnyWho
Find a US toll-free number.
http://www.anywho.com/tf.html

Canada Toll Free
Search for Canadian toll-free numbers.
http://canadatollfree.sympatico.ca/search/

Car Hire
Call American car rental companies for free.
http://www.myprimetime.com/play/travel/content/em_contacts5/index.shtml

Cheap Flights.co.uk
Telephone cheat sheet: skip the menu and the hold music, and get straight through to dozens of major tourism and travel companies.
http://www.cheapflights.co.uk/travel-tips/cheatsheet.html

Credit Cards
Toll-free telephone numbers of major credit card companies.
http://www.myprimetime.com/play/travel/content/em_contacts1/index.shtml

Get Human UK
Telephone menu shortcuts to customer service at major firms in the UK.
http://www.gethuman.com/uk/

Get Human US
Skip the muzak and get through to a real human in major companies all over the US.
http://www.gethuman.com/us/

Hotels
Toll-free numbers of major hotel chains.
http://www.myprimetime.com/play/travel/content/em_contacts4/index.shtml

Inter800
Search for American toll-free numbers by product, service or company name.
http://www.inter800.com/

John Cletheroe's USA & Canada Holiday Hints
The toll-free telephone numbers of US state and Canadian provincial tourist offices.
http://freespace.virgin.net/john.cletheroe/usa_can/phone/states.htm

Say No To 0870.com
Avoid dialling firms' premium rate telephone numbers by using one of the alternative standard rate numbers listed on this site.
http://www.saynoto0870.com/

The Freephone Directory
UK directory of freephone telephone numbers.
http://www.freephonedirectory.com/search.asp

Yellowpages.co.nz
Just click on the links marked "New Zealand - Mobile and 0800 numbers" at the bottom of the page.
http://www.yellowpages.co.nz/