jbeltmen brought to my attention a bunch more geomorphs from various blogs. Most of these are dungeony, but they all have some cave systems.
original edition fantasy
hereticwerks just has a bunch of stuff
planetalgol (Planet Algol guy, where did you go?)
dagwood sandwich (This is a BIG pdf full of maps)
fighting fantasist (these are all 'square' so more dungeony)