Here in Austria, I also think it's hilarious how cookbooks always lists "beef stock" in the ingredients, and then refer to a recipe for beef stock, but in reality everyone just uses soup powder (which is mostly salt, MSG, and fat).
And the funniest part is how some people claim they don't tolerate Asian food because of the glutamate, but when they eat at traditional Austrian restaurants they have absolutely no issue with all the glutamate in the beef soup.
Or how every steak restaurant has the chefs secret spice mix which is basically just some herbs mixed with a generous scoop of MSG.
Supermarkets don't have a lot of things here in Berlin. But there are plenty of Asian stores. I bought some MSG a few months ago in a Pakistani shop that also sells a lot of other nice things that you are unlikely to get in most German supermarkets. If you are in Berlin, the shop is called Tariq and it is near the Gesundbrunnen station.
Here in the USA it is most commonly sold on store shelves as "Accent". Worth noting: MSG is naturally occurring in some foods, such as cheese. And if you salt a tomato slice, a lot of MSG is produced.
I could have sworn that one of the usual suspects - Ostmann, Fuchs.. - used to sell it in small shakers you'll find in supermarket spice racks, but those seem to have disappeared.
You can buy it by the kg from Metro/Selgros, though.
Any asian store will have it (as vetsin, for example). If you're really hard-pressed, you can go to the netherlands and buy bulk amounts from an asian store there.
I saw some for sale last time I was in an Asian shop here in Freiburg. Sold in 1 kg bags, looked like salt, made in France (which surprised me the most).
