Good job Mr. Poke. :)

You're actually quite lucky the VG community is far friendlier than others. In SOME other communities, being open and honest about your professed noobness would have you hunted down by the 'pro' pack.
Anyway,
Your Cath build is a lot like what I do! I usually get a Contraption, Fountain, Crucible, Aftershock, and of course boots. That empty slot is either taken up by an early Atlas Pauldron or Warhorn. Catherine should gank at every opportunity (to gain passive stacks). And lastly, you forgot the last and utmost rule! NEVER SURRENDER.
I'm sure you'll elevate yourself past noob level.