How to trace Websites Web Host

Hi,

A company has stolen some testimonials that I have worked hard to get for a product I am selling - and is using them on their site for a differerent but similar product!

I have contacted them - ignored me - and now sent them a 'Cease and Desist' order.

I am trying to trace their web host so I can send them a letter, but after 3 hours have failed.

Can anyone advise me of an online tool that I can use?

Many thanks in advance for any help,

VSC

Hope this helps