There is no name for attendants of Oktoberfest. You might call them Volk or Teilnehmer.
Because the month in which it takes place is october, called "Oktober" in German.
Germany has the really famous Oktoberfest. There are many local events called Oktoberfest in the United States, and probably in other countries as well.
It is called the Oktoberfest.
As far as I know, there are no other names for Oktoberfest, that is if you meant the annual festival held in Munich. However, for other versions of Oktoberfest held all over the world, I am sure they make have slightly different names. Otherwise, mostly it is just called Oktoberfest.
I think you mean the "Oktoberfest"
Oktoberfest is a 16- to 18-day festival held annually in Munich, Germany, typically starting in late September and ending in the first week of October.
An Oktoberfest horn is a tuba.
In Germany one of the customs is Oktoberfest. Oktoberfest happens every year and thousands of people come from other parts of the world to participate.
Somewhere around 6 million
The drinking vessels used at the Oktoberfest is called a Krug (jug). They are made out of thick glass and hold a litre of beer (a Moaß - eine Maß - lit. measurement).
If the person is a friend you say: " Wir hoffen dich auf unserem Oktoberfest zu sehen". In a formal context: "Wir hoffen Sie auf unserem Oktoberfest zu sehen". Plural version informal: "Wir hoffen euch auf unserem Oktoberfest zu sehen". Plural formal version: "Wir hoffen Sie auf unserem Oktoberfest zu sehen".
Oktoberfest is as always in October! Prosit!