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http://udn.epicgames.com/Three/DevelopmentKitHome.html
Just focus on UnrealEngine3 not 2. And the name of free version is called Unreal Development Kit (UDK).
You can download the engine for free:
http://udn.epicgames.com/Three/DevelopmentKitGettingStarted.html
There are books in Amazon too: "Mastering Unreal Engine". There are several volumes and several editions. Try to find the latest. As far as I know this book series doesn't cover Unreal Script. You will need to find other books that cover it or you can find the reference page here:
http://udn.epicgames.com/Three/UnrealScriptReference.html
There is also video tutorials which is an easiest and efficient way of learning a tool:
http://udn.epicgames.com/Three/VideoTutorials.html