Hmm, sorry to hear about this!
I've always found either Tesco or Admiral to be the cheapest for me. At 19, I was with Tesco.
I'm with Greenlight now, and they were by far the cheapest quote, but I have a sneaking suspicion that you are too young to qualify for a decent quote with them, although give them a go definitely!! I am quite possibly wrong.
Other than that, Adrian Flux are also ok with younger drivers, as are HIC on occasion.
Best of luck mate,
Chris.