I want to make sure I have this right (or... wrong).  Can I stay roughly 9 months on one of these multi-entry tourist visas if I leave just before the 6 months expires (in other words I get an extra 3 months, assuming 30 day extension)?  I need to go ahead and buy a round-trip ticket, so I want to know how these things work and how long I can stay.

 

Thanks.

You can get almost 9 months of total stay by doing what you wrote about.

How long you can get depends upon when you apply for the visa and have it issued. The 6 months starts from the date the visa is issued.

What if I get that 9 months, then leave.  Can I come back on a 30 day VOA (I'm American)?  In other words, get roughly 10 months?

You could get a 30 day visa exempt entry (you do not qualify for a 15 day VOA) that could be extended for 30 days at an immigration office after the METV.

Do I get the visa exempt entry upon attempting to enter Thailand?  Or is it something I get in another country like Cambodia or Burma or whatever?

You get it on entry to the country. There is nothing to apply for just line up and show your passport and arrival card.

You can get the 30 day entry by land, sea or air.