Welcome to the forum . We've been through this subject a few times on here!!
The V6, although a brilliant engine is normally quite "tappy" at tickover. I went through the same thoughts when I bought my V6 five months ago.
In the end, I took the car to my local Alfa speciast, who assurred me all was normal.
So unless its especially bad, don't worry too much.
Its probably worth just taking a while to sift through a few old posting on this forum.
(I'd direct you to them if I wasn't at work now!!) eek!