There are thousands of affiliate programs available one should choose the best program that suits your site and visitors interest. Here is a list of some of the best affiliate programs available, read about user policy and mount of revenue and commission you could earn from each program before applying.
Expedia Affiliate Network
Priceline
Tripadvisor
Orbitz
Travelocity
Hellotravel
Hotwire
Tripit
Hotelscombined
Now if you are running a travel website that has more traffic inclined towards travel equipment and shopping-KAYAK affiliate programme is a really good way to convert traffic into revenueKAYAK