First Groovy Script

A couple days ago I wrote my first Groovy script. Of course it had to be loaded into the Spring IoC container to wire it up to the beans using it.
Having a Java background and looking at Groovy's website it was very hard to define a pretty simple class with a method that implements a java interface.
First it made me use the def keyword with the method definition whereas the documentation didn't even have an example of how to write a method.
Then it made me define the return type of the method because it was saying it didn't match the interface return wheras the documentation seemed to indicate these did not have to be statically defined/typed.
The method took in no parameters and returned a List and was returning [instanceofMyObject1, instanceofMyObject2]
The documention showed defining typeless variables without using the def keyword.
It kept looking for member variables in the class so I had to define each one with the keyword def to get it to work.

Is the Groovy documentation really lacking good basic examples like writing a class with a method and using local variables?

The documentation outlined some of the power features but did very little to help people learn the basics other than go over some command line Groovy examples.

Can people recommend some good resources for a Java developer to learn and effectively take full advantage of the capabilities of Groovy?