Besides Pilot guides I use three basic ones at least before fine tuning. Maybe you guys have more suggestions?
One is the "World Cruising and Sailing Wiki", made by all cruisers and that is becoming big and very useful.
World Cruising and Sailing Wiki - a Cruising Guide on the World Cruising and Sailing Wiki
The "old" noonsite is also a reliable source of information:
And in what regards interesting places, the best come on the World Heritage site:
UNESCO World Heritage Centre - World Heritage List
Like many, I am preparing summer cruising so if you guys know of more great sites that provide cruising information for sailors on the net, please post