As of right now, you cannot get a 1 year tourist visa.
@Brandon ***********
is right, a multi entry visa is your best bet. But that would also suggest to immigration that you need the multiple entries.
Also, you would definitely need a departing flight in order to get the visa.
You could also come in on the single entry tourist visa, extend, and then go travel to a different country, then return visa exempt. Your life would be easier if you are moving around Thailand, not staying at 1 address though.
But bottom line, whichever tourist visa you use, you will need to leave Thailand several times.