Hi - It is certainly worth going to a LDS Family History Centre to see what they have freely available on the spot (on film, fiche, CDs and sometimes Ancestry and other online websites), as well as what you can order to view (usually on film sent in from Salt Lake City - parish registers, wills, etc.). If you go to the "Library Catalog": on the FamilySearch.org website you can find exactly what places and dates are available:
www.familysearch.org/eng/Library/FHLC/frameset_fhlc.asp

For England BMDs the most accurate indexes available are transcripts from the local record offices, such as: cheshirebmd.org.uk/ and www.lancashirebmd.org.uk/ (see those for coverage, which varies). General information is given on: www.ukbmd.org.uk/
The GRO indexes are copies of copies and have a lot of mistranscriptions (in the original volumes) and omissions, but can be searched across all counties. See: www.freebmd.org.uk/
The IOM equivalent is www.manxbmd.com/ which takes patience and can be difficult to decipher, but is usually worth the effort.

Unfortunately the marriages on FreeBMD are still being transcribed, and it looks as though they have completed almost all years up until 1949, and are yet to start on 1950-1969. However they have been amazingly quick with uploading these over the last couple of years so we may not have to wait long for the next 20 years.

You can also look at the index on www.findmypast.co.uk for free. The only marriage which has the forename and both initials is:
Last name First names Registration district County Registered year Month / quarter:
MOORE Philip A J Surrey Northern Surrey 1955 Jan-Feb-Mar
Others were:
MOORE Arthur P Bristol Gloucestershire 1953 Apr-May-Jun
MOORE Arthur P C Wood Green Middlesex 1954 Jan-Feb-Mar
MOORE Arthur P Ledbury Herefordshire 1956 Jul-Aug-Sep

At this stage you need to pay to see further, or have a subscription.
Is this the right marriage?

Name: MOORE, Philip A J
Registration District: Surrey N.
County: Surrey
Year of Registration: 1955
Quarter of Registration: Jan-Feb-Mar
Spouse's last name: Craymer
Volume No: 5g
Page No: 951

Name: CRAYMER, Melanie A
Registration District: Surrey N.
County: Surrey
Year of Registration: 1955
Quarter of Registration: Jan-Feb-Mar
Spouse's last name: Moore
Volume No: 5g
Page No: 951

They also have scans from the GRO index pages to check that the transcript is correct.

You can order this cert online from the GRO with a credit card:
www.gro.gov.uk/gro/content/certificates/
See “Order a certificate online now”.
Then: “First time users, please click Registration below”.
Make a note of the password you choose (and record whether lower or upper case on each letter or they will reject it if you get it wrong the next time).

If the above is the wrong marriage I'll try the others for you if you can give me the name of who he married?

Sue