migrating LR3

[Kofman13]

I do all my work on a macbook unibody aluminum 2009 which is running 10.5.6 leopard. i am in the process of backing everything up and doing a clean install of snow leopard and starting anew so to speak.
90% or more of my workflow is done in Lightroom 3. all my photos are imported there i have countless of pricessless actions etc etc. Lightroom3 is my life pretty much.
Does anyone have any good methods of going around nicely and neatly backing up all my settings, catalogues, presets. basically i want to have the same lightroom experience i have now, in my new operating system install. just the way it was before.