There are three main sources of on-line assistance.

1. Frances Coakley's "Electronic Manx Notebook", which has a search capability, and houses numerous directories and monumental inscriptions (Feltham's Tour), can be very useful at:
http://www.ee.surrey.ac.uk/Contrib/manx/index.htm

2. The IGI is on-line at:
http://www.familysearch.com/
I use the IGI "custom search" pages, which can narrow down the number of hits

3. Several people have offered "Look Up" assistance with burial records, censii, (?), monumental inscriptions etc. Just make sure you are reasonably specific about the request at:
http://www.isle-of-man.com/interests/genealogy

From the IGI:
Offspring of William CROWLEY & Elizabeth CRELLIN

1. William COWLEY - Birth: Abt. 1743 Michael, Isle Of Man
2. John COWLEY - Christening: 30 Jun 1745 Michael, Isle Of Man
3. Catherine COWLEY - Birth: Abt. 1747 Michael, Isle Of Man
4. John COWLEY - Christening: 8 Apr 1751 Michael, Isle Of Man
5. Patrick COWLEY - Christening: 31 May 1753 Michael, Isle Of Man
6. Ann COWLEY - Christening: 22 Dec 1755 Michael, Isle Of Man
7. Nicholas COWLEY - Christening: 2 Apr 1758 Michael, Isle Of Man
8. Thomas COWLEY - Christening: 26 Apr 1761 Michael, Isle Of Man
9. Margaret COWLEY - Christening: 16 Nov 1766 Michael, Isle Of Man
10. Katherine COWLEY - Birth: Abt. 1768 Of, Kirk Michael, Isle Of Man

Wm COWLEY m Elizth CRELLIN 30 Jun 1745, Kirk Michael, Isle of Man

Wm COWLEY possibly

submitted relative of William Ernest COWLEY chr 30 Mar 1718, Kirk Michael, Isle of Man or
submitted relative of Charles Franklin COWLEY chr 29 Oct 1715, Kirk Michael, Isle of Man or
COWLEY Wm s/o Jon COWLEY & Kath MC YLECHARAN chr 28 Oct 1716, Kirk Michael, Isle of Man