When laptops with Windows 7 will be widely available in the UK?

When laptops with Windows 7 will be widely available in the UK?

My friend is going to buy a laptop very quickly but she wants to have Win7 rather than vista there. She could wait but not too long. When laptops with Windows 7 will be widely available in the UK? Or is it possible to buy a vista laptop now and update it to win7 for free? Thank you.