* What country do you live in?
Croatia
* Is beer as a product in general (commercial/non commercial) taxed in your country?
Only as a commercial product, based on alcohol content and capacity of the brewery (later one was introduced recently, based on Czech model of taxing smaller breweries less)
* Are you allowed to produce homebrew beer, that is tax free?
Yes,, as long as it's produced for personal consumption (family and friends included!)
* Is there some amount limitation of homebrew beer that you are allowed to produce without paying taxes?
None whatsoever.
* Is there any legal obligation considering for instance an obligation to fill a report or announcement as a homebrewer and send it to your legal authorities in order to be allowed to brew beer at home?
Nope.
Sadly, I'm not familiar with specific legislation concerning homebrewing in Croatia, so I can't offer more details.
However, as I live in a part of Croatia that's home to a large Czech minority community, I know for a fact that tradition of homebrewing is something highly regarded by them (as it should be), and just a generation or two was "business as usual" in a household (mostly done by women). Few years ago, when I announced that I brew my own beer, to my great surprise, I was shown recipes and advice written in old notebooks by aunts and grandmas.
As a great fan of Czech brewing tradition and beer, I'm sorry to hear that you are facing such difficulties. Homebrewing is a great, multidisciplinary hobby, fulfilling in every sense of the word. Also, here in Croatia it's recently been shown that it can be a driving force behind small enterprises, and an appealing addition to our tourism industry.
Of course, small breweries and beer tourism is something that's taken for granted in Czechia for a long time. However, I think that restricting homebrewing in a country with such a rich brewing history is deplorable, and is also restricting innovation and discouraging young people that show interest in brewing by completely unnecessary legal complications.
In Czechia, a country that gave us, and is still giving us, some of the best beers in the world, homebrewing should not only be accepted and unrestricted, it should be encouraged and celebrated!