I should have put this in my previous post but there are some great wiki's keeping up to date lists of budget airlines. I prefer WikiTravel to Wikipedia for travel related info. The wiki's are kept current by smart folks like you and I that go in and edit incorrect info. Be sure to contribute if you notice anything wrong or add anything missing!
Global List of Discount Airlines
WikiTravel:
http://wikitravel.org/en/Discount_airlines
Wikipedia:
http://en.wikipedia.org/wiki/List_of_low-cost_airlines
Asian list of Discount Airlines
WikiTravel:
http://wikitravel.org/en/Discount_airlines_in_Asia
European list of Discount Airlines
Wikitravel:
http://wikitravel.org/en/Discount_airlines_in_Europe