Hi Diane,
If you click on Family History Society tab same page as Manx Genealogy tab, this takes you to many items and the publications page. If you know your home / ancestors parish you can purchase Mi's / burials / and Census's books.
Obtaining parish vicars address,s I am sure the Manx Museum will help see below.
Library Assistant
Manx National Heritage
Kingswood Grove
Douglas, Isle of Man, IM4 3LY
Tel: +44(0)1624 648000
Fax: +44(0)1624 648001
Website: www.gov.im/mnh
"Good Luck"
Brian www.kneen.com