WikiIslam is excellent!
I want to mention a tactic that I believe is very useful in the fight against Islam. Time and time again I come up against the old "but what about the peaceful Muslims?" line.
I have found that one good way to defuse that is to point to France (with its 751 "ZUS zones" — the no-go areas that are very dangerous for non-Muslims).
These zones were set up by the so-called "non-violent" Muslims.
All they had to do was to move into an area in large numbers. Property values then drop (allowing even more of them to move in). The locals moved out and presto — a part of the country is conquered. No guns or bombs needed.
Heck, the French government even has the ZUS zones on its website! This PROVES that these zones — set up by the "non-violent Muslims" — are dangerous.
Two links about these zones: