USA:
National Geodetic Survey Markers,  How to find them?  (All for no cost)
NGS Markers: How Accurate are they;  First-order, Second-order,...etc.

Canada:
British Columbia, MASCOT GSM Markers in BC,  How to find them?
For Canada,   you can also obtain info on survey markers from the
Geodetic Survey Division of Natural Resources, Canada
Canadian Survey Markers:  Map with detailed information (Free)
Buy Scanned Topo Maps for Canada here

Australia:
Survey Marks Enquiry Service via the Internet

New Zealand:
ASP, Geodetic Database, Geographic Place Names Database

Spain
COORDENADAS UTM DE LOS VÉRTICES GEODÉSICOS ESPAÑOLES

United Kingdom (aka England)

Triangulation Pillar Waypoints in the UK

Well..  This may NOT be a WorldWide listing YET,  but if you will send me a
LINK for "where to find them" for YOUR part of the world,  it soon WILL be a WorldWide listing.

Thanks
Joe Mehaffey