Try JR Whippet rescue, Lynda Jones 01234 838927 really the only dedicated whippet rescue, but with helpers nationwide. As far as I know they still don't have a website tho
You really need to contact as many rescues, grey/lurcher/all breed, as you can find, as JR have a long waiting list, and whippets don't always end up in their care anyway.
Occasionally a rescue whippet will pop up here: www.k9community.co.uk ....worth a look?
The Dogpages forums constantly have new dogs added, so you could check there regularly, or contact a rescue near to you. K-Nine seem to be in Huddersfield and have had a few whippety types recently.