They're everywhere here.
Remember though they're banned in all national parks and i see people fined on a regular basis.
Don't fly it over crowds, crowded beaches, temples and so on.
Remember Thailand is a strict military dictatorship - the police and military are all powerful and anything "security" related will be heavily frowned upon so don't go flying it near police stations, military bases or anything else. Be aware of your local area via google maps and so on before flying as "i didnt know" is no defence.
Technically drones need to be registered but the system doesn't work at all, its ground to a halt and nobody is bothering (and nobody who has tried has managed to get anywhere).
Ultimately, if you behave and fly considerately away from crowded areas, national parks and so on there isnt an issue.