You don't say where you live, but guessing that you are in the USA, try
http://www.emperorlinux.com/
Being a Brit I have no experience of them - I happened to come across their ad in a Linux magazine.
For fellow-Brits who might have the same question, try
http://www.linuxemporium.co.uk/ . They sell IBMs with your choice of distro. But, there is another company:
http://www.laptopshop.co.uk/ , who are selling the same IBMs, but with Windows, cheaper.
You might want to shop around bussandtech. You might find that Windows pre-loaded machines are cheaper where you live. That's the nature of the market.