Thanet Pays are quite numerous on the IGI and you will find more on the familysearch site as they have just put the 1881 UK census online http://www.familysearch.org/
The 1901 census now works at the PRO site and is very useful as you can search by place name.
The http//freebmd.rootsweb.com/cgi/search.pl site also allows you to look for Pays by location.
You probably knew all that but as some of it has only been available for a couple of months you may find something useful.
The easiest way into it is to find someone in the 1901 census you know of - preferably someone living with their parents - or to identify someone whose birth certificate or marriage cert will get you back pre-1901.
The Ramsgate Pays are a bit of an unknown to me - I havn't typed them into the computer yet. Its not clear if they were there always (for this purpose pre 1700) or moved there from earlier groups of the family which seem to have been in the valleys around Canterbury and Folkestone. There are a lot of 18C Minster (village) Pays who lived on the border of Thanet but only a few miles from Ash where there were Pays in the 1680s - not clear which was chicken and which was egg or whether there are two flocks. Thats the basic problem with the Pays - they live in discrete areas but then everynow and then move exactly to where supposedly distinct groups live. To complicate matters further there is a line of Sussex Pays who drift to Shropshire and then come to Folkestone in the early 18C. Unfortunately (or fortunately for you if you are related to one as their lineage is pretty clear to 1420!) one group of these decamp to thanet before the 1881 Census. The Thanet Pays in turn seem to react to the railway and you will find them moving out to the Medway Towns, London and Sandwich, Essex and even further... as the 19C moves on. Have a look at the 1901 census and then the 1881 one with a name in mind and see who you find. Glad to help if you get stuck. If the Pay of Ramsgate you link to is shown as being born in Folkestone or Dover I will point you to the line back to 1420.