Can I (USA) get a tourist visa at the Hanoi airport similar to how it works here in Thailand? Lots of internet sites want to "sell" me the form but I think I can just get it at the airport and fill out there. Recent experience anyone?

 You need to get an "official Vietnam Visa Approval Letter" from one of these sites (e.g. https://vietnamvisa.govt.vn/).

 With this letter, an NA1 visa form, photos, passport you can get a visa on the airport (subject to additional fee).

I am USA citizen, recently applied for tourist visa per the above URL. That one is the official VN gov't, very clear and simple. Follow the steps, pay the application fee, get a email back from them with form to you have to fill out upon arrival in VN. That and pay US$25 at the airport for this "stamping fee". Also need 2 photos with that form. 

Thanks for the info. I was just beginning my search to see how to do this. I'm headed to Hanoi later this month.