You will need to arrange your visa beforehand.  Prior to going to Vietnam, pickup the Vietnam visa at an embassy in the country you are in at that time. 

 A free, 30 day visa is available on arrival at the airport for most nationalities (all Western countries included).  For entry to Thailand by land, a free, 15 day visa is available on arrival.  If you want to stay for 60 days, you will need to apply for a visa at the Thai Embassy.  Citizens of Argentina, Brazil, Chile, Peru and South Korea are able to stay for 90 days.

A free, 30-90 day (depends on your nationality) visa is available on arrival at the land borders and at the airport.  This applies to all western countries.

 A free, 21 day visa is available on arrival at the airport.  You can apply for a 59 day visa ahead of time at the Philippine Embassy in the country of your choice, or, you can extend the 21 day visa once you are in the Philippines.

You need to get your visa ahead of time.  Currently there are no land borders open with Myanmar and its surrounding countries.  You must fly there.  28 days is the visa limit in Myanmar, however, you can extend this once you are in the country – for a further 14 days. 

30 day visas are available on arrival at any land borders and at the airports.  If you pay in USD the visa will be a bit cheaper, if you pay in Thai Baht, it will cost you a bit more.

A free, 72 hour transit visa is available at the border with Sabah and Sarawak (Borneo).  If you wish to stay longer, you will need to apply for a visa, costs and lengths of stay vary widely depending on your nationality.  

A 30 day visa is available on arrival at the border and at the airport in Laos.  The price of the visa varies depending on which country you are from. 

A free, 90 day visa is available on arrival at the airport and at the land borders.  This applies to most, if not all, western countries.  The 90 day visa includes Peninsular Malaysia and Malaysian Borneo.

A 30 day, visa is available on arrival at the seaports and airports in Indonesia.  The cost is $25.  You can extend your visa when you are in the country for a further 30 days.