Is there a website which highlights airport locations on a map?
SkyVector is a great resource for aviation maps and data of all kinds. It offers worldwide sectional- and low-ifr-type charts, and a fully-featured Airports section.

I'm not sure if you also want airport diagrams, but you may also get some decent results with OpenStreetMap. The open source maps have some hit-or-miss levels of detail for airports, some including full taxiway and runway data. Others are just property outlines.