Question : How map  network PC's to <a rel="nofollow" href="http://www.company-name.co.uk" target="_blank">www.company-name.co.uk</a> when the INTERNAL domain is the same?

I inherited a network that had been named company-name.co.uk (I usually use company-name.local) Now, when the network pc's goto www.company-name.co.uk it resolved back to the AD server. I know it's a "c-name" (or something) issue, but I'm un sure how to apply it to "point" to e.g. 82.56.43.123. Could somebody give me a short step by step?
Its a Windows 2003 AD set up.

Answer : How map  network PC's to <a rel="nofollow" href="http://www.company-name.co.uk" target="_blank">www.company-name.co.uk</a> when the INTERNAL domain is the same?

You actually need a host record, not a CNAME record.  Just create a host record named www on your internal DNS server and give it the 82.56.43.123 address.  Of course, if you happen to have a machine in the internal network named www...well, you've got problems.