What are my options for staying longer in Thailand after multiple visa runs with an American passport?

and I believe on that note

@Co***

has more than enough information to make an educated decision as far as how to further their stay in the glorious "Land 'O Thaiz".

Like Greg Lewis, correctly stated there is no limit of 30 day visa exempt entries when flying in and there is a limit of TWO 30 day visa exempt entries by land.

You could go to a land border stamp out of thailand, stamp in&out of another country and then stamp back into thailand to get a new 30 day visa exempt entry stamp which you could then extend for 30 days at the immigration office like you did before for 1900baht

OR

As I suggested, go to a thai consulate in a nearby country and get a single entry tourist visa.

You're not going to be able to live here on endless 30 day visa exempt entry stamps and extensions because at some point the immigration officers at passport control will question you about it

Did you actually go to a thai consulate and BUY a visa for thailand?

You can only get TWO 30 day visa exempt entries by a land border crossing in a calendar year.

I would say go to a thai consulate and buy a single entry tourist visa for 1000baht. That'll stamp you in for 60 days and you can extend that by 30 more days at the immigration office for 1900baht

it sound more like you entered the country on a 30 day visa exempt entry stamp and then border bounced to get another 30 day visa exempt entry.

yeah you're not actually doing "visa runs" because it sounds like you haven't gone to a consulate and BOUGHT a visa for thailand.