Hi guys,

I apologize in advance if this isn't in the right forum... I'm new to the site.

So I am trying to book my first ever award flight, and the number of options are a bit daunting. Here is my situation:

I am looking to travel to Thailand / SE Asia from about 12/15/13 to 1/12/14 and would want to take advantage of a free one-way flight, probably from 3/15/14 to 3/23/14. I would be flying out of ORD and probably to BKK. Also, I don't need or want to travel in anything better than economy.

I have the following airline / reward miles:

AA: 68,900
United: 66,500
US Airways: 40,000
Delta: 24,000
Chase Ultimate Rewards: 49,000

Can you give me some tips on how best to book this tentative itinerary? Some questions I had are:
- What airlines offer free one-ways?
- What are the limitations on them? How far can I go on a free one-way?
- What sort of change fees are involved if I want to change the date of the free one-way, both before and after flying the SE Asia portion (if possible)?

Thanks