I am working on a game, but right now that terrain just stops. I would like to make a bigger terrain. I thought if the terrain repeated like tiles that would be all I would need. Does anyone know how to do this?
You should find quite a lot already written on the forums about this sort of thing.
Two topics below are systems for very large scale terrains, and some of the replies have more good stuff.
If you don’t want to delve into them or need that sort of scale, there’s no reason why you can’t create a simple tiling system using terrain blocks as tiles. I think some people have chosen that approach.
http://www.jmonkeyengine.com/jmeforum/index.php?topic=9880.0
http://www.jmonkeyengine.com/jmeforum/index.php?topic=5170.0
OMG i'm getting props 
thanks alric
currently if you just use the default implementation for my terrain, its actually infinite based on a perlin generator.
and its editable too, saving only edited blocks while the rest is generated, thats my basic idea.