Retrieving Wikipedia's coordinate information?

See the database dump section on http://de.wikipedia.org/wiki/Wikipedia:WikiProjekt_Georeferenzierung/Wikipedia-World/en. This gives the option for a PostGIS connection.

There was also a CSV download option at one time but that seems to have been removed sometime between 2011 and 2016.

Also look through http://en.wikipedia.org/wiki/Wikipedia:WikiProject_Geographical_coordinates for other options.

An API solution is probably your best bet, but if you are dead-set on using the database dumps, in this Twitter response the WikiLocation API author explains a bit that he is not scraping the entire Wikipedia database dump but only certain tables.

I would start by looking at the external links database and looking for the links to GeoHack (probably only ones matching the pattern used by such URLs as the Sydney one).