Yes, that was 3 wives.

I'm not sure what you're asking about recording offices.
Prior to mid 1870's Manx records were kept by individual parishes--baptism, marriage, burial.
Online the IGI on the familysearch.com site roughly parallels this period
After that time, civil registration by parish of birth, marriage, death.
Brian Lawson's site has some of this info including wills.
http://www.lawsons.ca//home.html

The Manx Museum and other records repositories have the records.

The Mormons have microfilmed most of these records and they are available for minimal rental from the various Family History Centers.