Nyrva, I'm a new player as well and had also been wondering the same thing, specifically about Events. I couldn't find any consolidated info (for dates) so I went through the forum, looking at past Events (both Main and Questline), and made a list. It should help to give you a rough idea of when to expect new ones.
ver.2 of the list/document can be viewed
HERE.
This one looks a
little nicer and is in .pdf format (which resolves the previous formatting issues).
--------------------
Click
HERE to view the list.
It's an .rtf document, uploaded to my Dropbox.
If you'd like to download/save it, click the "..." in the top-right and then select "Download".
EDIT: Uploading to Dropbox seems to have messed up the formatting (of some of the banners) in the online view, but the downloaded/saved document should look fine, with the center formatting.