What do we need and where should we go for a visa extension from visa exemption in Thailand?

Visa Exempt entry gives you 30 days and from there, you are allowed to Extend one time ONLY for an additional 30 days... YOu just need a Passport valid for 6 months

Your nearest immigration office (you dont say where you are)

You will need copies of passport page

T6 copy and copy of entry stamp.

One passport photo.

The form to fill out can get there, there is also at most immigration officea somewhere close if not on premises to copy and take photos.

1900 baht.

Think thats all long time since i done one

Immigration office in Phuket Town.