1. "Now for the final round."

2. "Now for inaugural ceremony."
Is "Now for" a standard way of announcing the start of an event or is it a part of a bigger sentence
as in "Now for the inaugural ceremony I would like to call Mr X." or "Now for the final round please take your seats."

The expression can be used in both ways.

Debpriya DeCan "Now for + event" stand alone as sentence ?
It can, even though theoretically it's not a complete sentence. Think of it as something like "Hello!", "Sorry!" or "Me, too", which are similar in that they too are not complete sentences, but they are used frequently as independent expressions.

"(And) Now for" can be paraphrased by "(And) Now it's time for" if you want to know the underlying thought.

Students: We have free audio pronunciation exercises.
Can "Now for + event" stand alone as sentence ?
 CalifJim's reply was promoted to an answer.
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