I'm sure my answer may be in this forum somewhere but I thought I'd post anyway. Sorry.

I have a tourist visa that I'm looking to extend. I'm living in Chiang Mai and have stayed ~2months on this visa. To get it extended Do I just go to the nearest immigration office, pay 1900 baht and have it extended? Is this all? Is the process difficult? Meaning am I guaranteed an extension and/or should I goto the immigration office early because of big lines, etc? Thanks.

Go to immigration with a photo and 1900 baht. Lines will be long if they are busy. I can't imagine you'd have to wait more than a half an hour for an extension.

Just make sure you go before it expires.