Belgian (& Italian) taxation (Antwerp)

Hello everybody!
I have a couple of questions about Belgian tax system, maybe someone who already went through all this has some useful advice to give.

I received some weeks ago a form from the government for the tax declaration (year Protected content . Apparently this is something everybody (I mean, the locals) fills in on their own. As a foreigner this is not exactly easy. I've been told there's an office where they help you with this.
Does anybody know how this works and what kind of papers I need to provide?

Second question (maybe for the Italians only...): I need to submit a tax declaration to the Italian fiscal office as well, but only afterwards. Any idea of how the all matter is arranged?

I'm sure I'm not the first one in this situation, so any suggestion, tip, info, warning is more than appreciated!

Thanks!

Anna