The web based Whois lookup can be found under the Janet App Centre: Whois.
There is a WHOIS command line server also available for querying registrations under ac.uk and gov.uk. To submit a query, use the UNIX command:
whois -h whois.ja.net domainname.ac.uk
The database is updated on a twice daily basis.
If you have any further queries about the availability of a domain name under ac.uk or gov.uk please telephone Janet Service Desk on 0300 300 2212 or email firstname.lastname@example.org.