Google Just Another Big Brother

After IBM, Microsoft and Apple tried and failed to corner the market in everything electronic, now Google are having a go. Not only are they promoting email, operating systems and browsers, now they are tracking behaviour on the internewt to sauch an extent that after I recently searched for Garden Sheds, every second intenet ad I have been faced with has been a garden shed.
How long befor the police are using similar technology to analyse our behaviour and shadow our thoughts 1984 style?