The calendar of grants is now available on ancestry.co.uk. Ancestry transcribers have made thier own surname index of the calendar of grants from 1858 - 1941. The calendar of grants is the national probate index and anyone who's will or administration went to probate in those years is included in the index. You search by surname and then you can browse the transcribed results, you can put in the exact name and date of death (if known) but if you do it that way you invariably miss something interesting and so i suggest a general search for a family surname and see what you find.
Ancestry cannot provide copies of the wills and there is advice on ordering the copies, though rather than using the district probate registries , I find it often is cheaper and quicker to find out which record office was the depositery for the probate office, for instance, wills proved at Liverpool 1858 - 1962 are at the lancashire record office and copies can be ordered for the cost of photocopying.
Cheshire wills are available to order online at
http://apps.cheshirew...Epayments/search.aspx
Other country record offices may offer a similar excellent service and so it is worth checking out the CRO websites.