In a few months I will need to renew my license. How early before the expiration date can this be done? And what documents will I need? I was told in Pattaya they require the address verification form from your embassy or Immigration. Is this required here?

It can only be renewed after it's expired - no, I'm not joking...TiT. Yes, you must either have a current work permit or an address confirmation from your consulate.

Agree with the above. There are several threads in Pinned Topics sections, Pattaya has two, one for one year and one for the five year. Also, the Automotive forum has one, perhaps check there for current information. I got mine at Mo Chit in Bangkok, took the expired license, medical certificate, copy of passport information, copy of visa and entry information, and got a residence statement from my embassy because I'm not doing one year extensions.