Does anybody know if there is a particular form that needs to be filled out in order to do this?

Visas are not extended. The only one year non-b visa is a multiple entry visa that you would have to apply for at an embassy or consulate.

If you qualify for it you could apply for a one year extension of stay based upon working for a company.

A TM7 application form is used for all extensions. Download and print two sided: http://www.immigration.go.th/nov2004/download/pdf/tm7.pdf

Perhaps the word "extension" is misleading. I have a 3 month Non B visa that I received in Penang already. My employer has told me that we can go to immigration in Chiang Mai and change (for lack of a better word) the 3 month Non B visa into a One Year Non-B Visa.

Has anybody had experience doing this, and if so was there a particular form required?

Perhaps the word "extension" is misleading. I have a 3 month Non B visa that I received in Penang already. My employer has told me that we can go to immigration in Chiang Mai and change (for lack of a better word) the 3 month Non B visa into a One Year Non-B Visa.

Has anybody had experience doing this, and if so was there a particular form required?

You can get an extension of stay based upon employment ...your employer must provide you with all documents to do this. You will not be changing Visa types.

Immigration does not issue one year visas. I am sure your employer means a one rear extension.

Okay, thanks very much for this clarification. I really appreciate it. Cheers!