The last time I went to Bangkok I got scammed on my tickets to Vietnam and Cambodia. Is there a trustworthy flight company I could use to get the cheapest possible tickets? This year I will probably just go to Chang Mai and Koh Samuii- so domestic, might go to a jeighboring country though.
Yes, just go the site of the airline you wish to fly with and book it yourself. For Chiang Mai, there are a few airlines to choose from. For Samui, your options are more limited. Check a site like http://www.skyscanner.net which will show you the budget options as well.

airasia.com then create an account and pay by CC. Bangkok to Hanoi, HCMC, Phnom Penh, KL, Chiang Mai and a bunch of other places. To Samui it's Bangkok Airways or Thai Airways both at a premium, or fly Bangkok - Surat Thani cheap on Air Asia and transfer to the islands.

http://www.attitudetravel.com/lowcostairlines/asia/ Here you will find all the airlines which offer good deals often

thanks will look into airasia. How is the weather in July in Thailand? Would a flight to Bali be better?

You can find a listing of websites of cheap airlines operating from Bangkok here Fly to Bangkok And you can purchase online. Do it some time ahead to get the cheapest seats:
Edited by: marhas