There are multiple websites online allowing one to apply for an 'e-Visa' for Vietnam. Are they following the law or is it some sort of a scam?
There is a Vietnamese embassy in my city but it's much easier to do everything online.
For what it's worth (and for anyone who ends up here from a search engine) e-visas with Vietnam are actually a thing now (as in, government issued, not visa on arrivals).
As other posters have said, there are a lot of sites that are still trying to act like government sites but in the end these sites just issue pre-approval for visa on arrival.
It seems as though gov.vn is the Vietnamese government's TLD: not govt.vn. You can apply for actual e-visas at https://evisa.xuatnhapcanh.gov.vn/web/guest/trang-chu-ttdt .
I found this link not through a search engine, but instead by following links provided by the Canadian government (whose gc.ca domain I trusted!). Presumably if you don't trust a random poster online I would suggest looking at your own government sites and look for information for travelling to Vietnam to confirm the above.
Final price is just $25USD (plus I think a few dollars processing fee). Plus when approved, you get a PDF that you can scan straight at customs / immigration: you will not have to do any 'visa on arrival' stuff!
Despite that fact that many websites claim to offer them, there is no such thing as an e-visa for Vietnam.
However in addition to normal consulate-issues visas, there is a "Visa On Arrival" available, however this works differently to visa on arrival for most other countries.
In order to obtain a VOA for Vietnam for need to first obtain an official invitation letter, and this service is available via countless websites - some of them legitimate, some of them less so.
TripAdvisor has a very good article on Vietnam Visa on Arrivals and I would strongly suggest reading it before you decided if a visa on arrival is right for you, and before picking a company to arrange the invitation letter.
Be very careful when picking a company to use for this service - many companies go to great lengths to try and mislead you during the process. For example, www.vietnamvisa.govt.vn appears to be a legitimate Vietnam Government website - except it's not. The government domain is "gov.vn" - this website has nothing to do with the government and is trying to use a similar domain to mislead you.
This confused me greatly as well, because like @Doc mentioned in his answer, there are many websites trying to look more official than they are. But I think in general that is just a sales tactic, as the whole process really isn’t that complicated. Like he also said, it’s not actually an e-visa but for all intents and purposes it can be seen that way and the immigration procedure is fully accustomed to this. I successfully used one of these services as well just about a month ago.