David, if you are planning to look at land records the easiest to start with is the clear 1700s copy of the Composition Book 1643-1703.
In the Manx Museum the film numbers are RC1 and RC2, and this is written on the two volumes.
In the LDS Catalog it is called "Transcript of Manor Rolls 1643-1700" [LDS film no. 0106649].

It is divided by parish, and then by placename, or intacks, etc., followed by personal names, sometimes relationships, and other details.

Sue