I posted an advice on this... it will be out of the dungeon... eventually. Covers the basics of all the major home security options. The best way to find out the cost of things is to look up Security in the yellow pages and let your fingers do the walking, as there is so much out there and the prices vary hugely. You will need to assess your needs and your budget before buying into anything. Shop around, see what you need v's what is available, get as many quotes as you can. If you read the advice... when it gets up... and you still have more questions you're welcome to fire them at me.