Yes for VN - must get it in advance. Get it from the VN embassy or consulate closest to you.
Laos and Cambodia, you need visas but can get them on arrival
India - must get in advance. India contracts with travisa for all visas, go to the Indian Embassy website and click though to travisa from there.

Going through agents costs more - sometimes a lot more.

No visas needed for Korea, Japan, Taiwan

Thanks so much! So does that mean I need to go to a consulate to get the VN visa, but I can get the Indian visa online?

You can go to the Consulate or Embassy website to download forms to fill out for your VN visa. You can go to the embassy or consulate, but most people mail in their forms.

For the Indian visa, you must get it through travisa, which offers the forms online and gives you online tracking of your visa's progress.

Of course, you have to send off your passport in order to get your visa.

You can get a Vietnam visa-on-arrival letter as a PDF by e-mail through a Vietnamese travel agent like Tonkin Travel ($15 for a single-entry visa; $30 for a multiple-entry). Then, when you get to the airport in Vietnam, you take your visa-on-arrival letter to the visa window, fill out another short form, give them your letter, passport, and photos, and pay an additional fee ($25, as I recall). Shortly thereafter they call your name and give you your passport back with a visa inside. Then you go through immigration. Not the most streamlined entry process, but very easy.

What April is talking about is a pre-arranged visa.

You can get your Cambodian visa online for $25. or upon arrival at the airport for $20. The online Visa arrived the next day,printed it and attached to my passport.If you do it upon arrival, you need to bring a passport size photo along.

If you arrive in Cambodia without a photo, they've been known to scan your passport and use that. I think the fee is $1!

Absolutely - Cambodia doesn't care that it's an "official" passport photo - any small photo suffices.

HappyTrvlr--did you feel comfortable giving your payment information out on the Cambodian visa website? I checked it out and it wasn't a secure website (usually begins with https), so I was kind of wary, even though it seemed like the easiest way to get it...

Again, it is just as easy to get your Cambodian visa when you arrive at the airport, and costs $5 less than doing it online.

Take a passport type photo (or a $2 bill) and hand it to the agent. You will be out of there just as fast, and will not have to deal with any website, secure or not.

India and Vietnam and the two that have to work for.

Thanks guys! I may just get a pre-arranged visa for Vietnam through Tonkin Travel (seems like they have a good reputation on the forum), and drop India altogether. And save the Cambodia visa for when I arrive, as it seems relatively quick and simple.

Seems like from what everyone is saying, I'm better off saving India for another trip so I can focus on it and not get too overwhelmed...I'm just now realizing how much of a load Japan, Korea, Taiwan, Laos, Cambodia, and VN are already!