I think I saw a similar post somewhere else. One of the real keys will be hooking up with some other cat sailors to help you. Probably learn more in a weekend with them than all summer by yourself. Also, you can read up on it. Get a copy of Rick White's and Phil Berman's books as well [both are available at the catsailor online store].

As far as boats go, personally I think an TheMightyHobie18 might be a better first boat for someone your size. Up front investment will be significantly lower and parts and sails, etc. are going to be easier to find and less expensive. Its still a lot of boat for someone new to sailing, so don't take it lightly - you can find yourself in big trouble in a hurry.

Sail it for a couple years, and then you can think about upgrading. H18s (in good condition and well maintained) seem to be in the flatter part of the depreciation curve, so you could probably sell it for close to what you buy it for and then put the money into an upgrade.

This is the path I took and it seems to be working for me.