Are they available over here like they use in other countries?

Im sick to death of women/elderly drivers. Im currently going through a claim which has been going on nearly a year now, where some old woman smashed into me and then denied fault. Suffering with the injuries still and out of pocket only the next day did a woman decide she wanted my lane on a dual carriageway and took the wing mirror off my courtesy car.

Had a few other close ones with women/elderly drivers.. must be what you get for living in a quiet village. However today i was on a two lane dual carriageway in the right hand lane approaching a roundabout (which gave me the option of either going straight over onto the next stretch of dual carriageway, or i could have turned right onto the roundabout into a retail park).

In the left hand lane was a woman of around 40 years of age, no brake lights apart from one in the rear window ( i spotted her just on the approach to the roundabout) her options where to go straight over onto the next stretch of dual carriageway or turn left at the roundabout into the supermarket. What did she do? she completely cut me up on the roundabout and turned right across my path nearly took the front end off my car and proceeded to go around the roundabout nearly taking the front off another car entering the roundabout from the opposite direction and then drove into the retail park. Guy behind me nearly rear ended me and the horror on his face was priceless at what she just did, i came to a stop on the roundabout in disbelief and the looks i got from the people who were driving behind showed they felt the same disbelief in what had just happened. Wanted to go after her but id come off the roundabout before i realised what had just happened. Couldn't believe it.

Times like this you always avoid the accident, but then afterwards you wish you had just smashed into whoever it was to teach them a lesson. I mainly drive £1500 - £2000k cars that im not all fussed about, now having a dashcam would prove her at fault (as woman and the elderly always deny liability when usually it is them in the wrong) id get paid out on my car plus be able to buy it back put a new bumper on it and hey ho free car which i can always sell on at a later date at the expense of some bitches stupidity. I wouldn't go chasing injury solicitors because im not that type of guy, i just feel some people need to be taught a lesson on the roads, some people are so away with the fairies high up in the clouds its unreal. I know it puts everyones insurance up each time someone claims but just because one of us doesn't claim isn't going to make it any cheaper for us.

Are dashcams easy to fit? Is there any sort of law or anything regarding them, would i need to inform my insurance. I don't want one that records sound just video. Curious how they work. Cheers