The following links and resources may be of interest.
Please let us know of any more that would be worthwhile to add.

New Zealand Army Website
http://www.army.mil.nz

Royal Tank Regiment Association
http://www.royaltankregiment.com/en-GB/aboutrtrassociation.aspx

1st Armoured Regiment Association RAAC
http://paratus.org.au

3rd and 4 Cavalry Regiments Association RAAC
http://www.3-4cav.asn.au/webdb/content/welcome-3rd-and-4th-cavalry-regiments-association-inc

NZMR Association: www.nzmr.org

QAMR Facebook: https://www.facebook.com/QAMR1864

Mounted Trooper Association https://www.facebook.com/search/top/?q=the%20mounted%20trooper%20-%20royal%20new%20zealand%20armoured%20corps