Yes, with links there are always problems...there are so many. That is why I decided not to make an enormous collection - there are too many allready. I gathered some starting points for beginners instead. If there is something you'd like to find, try Internet searchers. You should bear in mind, that different searchers are good for different searches - so don't give up after the first try!
If you are interested in geology, I'm sure that you'll find some good starting points under GEO - Science.