Thanks for that - bahtcoin look reasonable, I'll have to try for a small amount first and see how it goes 
No problem. I'd be interested to hear how it went.
Some more ideas:
I do know that there are meetups in BKK and Phuket at least. Check the meet up section on here and also meetup.com. From my experience you'll have a good chance to meet a seller at a meet up.
Also: https://localbitcoins.com/buy-bitcoins-online/th/thailand/national-bank-transfer/