If you are trying to find cheap flights to SE Asia or within SE Asia, there are many online booking sites that claim to get you the best deals.
One of the best sites in the region is 12Go.
They can find you good deals within the region with many of the budget airlines to / from Malaysia, Singapore, Thailand, Cambodia, Laos and Vietnam
Another flight comparison site you should visit is the ever popular Tripadvisor site.
They offer a good long haul flight search comparison, as well as a few of the budget flight routes in the region.
To find flight deals at Tripadvisor, use their flight search box below.