How do you say just a minute in German?

It is said Nine. yes nine as our number nine in America. Nine. Edit: It is spelled nein ;) but the other person is correct you say it like the English word nine

Wir haben funf minuten.

The word for minute is Minute! "Min" is pronounced the same as in English, "u" is pronounced like "oo", and "te" is pronounced like "tuh". So, try this: Minootuh... :)

Gerade ich bin

I assume you mean in the sense of browsing in a shop when you're approached by a shop assistant:Ich shaue/gucke nurorIch schaue mich nur um