8. Use consolidators for international business and first class fares.
Especially with the economic downturn, business and first class cabins will be emptier in 2009, and deals will be amazing. Consolidators specializing in premium cabins will have some great deals, and the airlines themselves will be heavily discounting their premium cabins, so check the specials on their web sites. Do a google search for "first class consolidators" to see some of the firms in this space.
See tip 9.