How do the police find out if you've been downloading & what are the fines??

I always wonder hoe they find you...
your personal computer as well as any other computer has what call an IP address. which can and is tracked by proper authorities when necessary if called for. Usually if this happens it is by an agency of some sort assigned to doesn`t matter what type of offenders they may be looking for.

there is nothing that you can do on your computer that can not be traced. Wew are adjectives. But I odnt think they really pay attention to the little guys... Unless someone is making major obvious damage you may go unoticed.. or better said not worth bothering with..
i do computers at school and i mull over it has something to do with the hard drive storing it contained by someway. And even you might delete those files etc later all the info will still be on the hard drive. I dont estimate you can really get rid of it for good thats how the police get you. As for fines, im not sure. It would depend on what the files be. If it were something really bad like child porn youd probably find arrested but like illegal music downloads you might have to salary the cost of what they would be back and/or maybe a couple hundred. usually the log on to the music downloading programs (lime wire/frost wire/etc) and look for people uploading music. not a soul has been arrested for downloading, they always achieve caught from uploading (so make sure you turn off your uploading capabilities) They use your IP address to track you.

here's an interesting story.... i forget what program it was, but the cops be on there trying to catch people, but in a minute the downloading company is suing them because their terms of service specifically state that the program can not be used for that purpose.

not sure what the fines are.
Most people that download things here and there don't receive caught. The people who do get caught are the ones that are sharing large amounts of songs's video etc.

They track your IP address. First they track it to your ISP later they get your home address and such from them.

The fines vary. The companies sue you for damages and copywright infringement. I believe i read a story that a lady have a few hundred songs she was actively sharing and was forced to pay $20,000 surrounded by fines. Jail time might also be possible.

It depends on the situation. I just read a lady was charged $9,250 per song for 24 songs she be sharing through a file sharing website. There was 1,702 songs but they only sued for those 24. If the jury found that she have willfully infringed the copyrights she could have been charged 150,000 per song.
They pretend to be music sharers. Then when you shared music near them, that's the sting. They get your IP address, from then on you are a marked man.