Are there any regulations in the UK for downloading things from torrents?

Using torrents is a perfectly legal way of sharing files and information.

However this legal system is abused by people to share illegal files and information ( songs, tv shows, movies etc...)

The best way of figuring out if what you are downloading is illegal is to ask yourself "Would I have to pay for this to get it any other way?" If the answer is "Yes. I would have to give the creator / publisher / distributor their fair recompense for my entertainment." Then you are downloading something illegally.

This (as I understand it.) is INTERNATIONAL copyright law and therefore illegal, even in Bulgaria.

EDIT FOLLOWING ADDITIONAL INFORMATION

iTunes, despite what Apple would have us believe, is not the only legal site to download music. Spotify, for example, allows free legal downloads because they operate an advertising revenue model. Your best bet would be to run an internet search for "legal music downloads" and then research the sites you find before downloading anything.

As for no-one getting sued in Bulgaria, I would suggest that it is only a matter of time. The corporate lawyers representing the music industry don't mind pi**ing into the wind as long as they are paid well for it.

Are you sure that copyright theft is legal in Bulgaria? that's what makes torrent downloading illegal in the UK.

I've not seen any torrent sites where you can pay to download illegal stuff... there are non torrent sites that you can pay for in the UK.