I have a dream in Z gauge

[Steamtrains]

Hi Mike.....I suggest you get yourself a Marklin catalog (Z-gauge, of course..), the complete version, so you can check out all the equipment they have for putting together a layout. There's probably everything you can imagine, and somethings you haven't thought of, in there. As I recall, they also furnish a price list with it, so you can get an idea of what you're looking at in terms of the $$'s involved. There is a section in there showing multiple configurations for the track arrangements you might want to look at as well. I believe MicroTrains is also manufacturing Z-scale items, so you can check it out as well. Another option is eBay. You can find hundreds of items there at prices that are quite a bit less than list price.
Good luck with your project, and keep us posted on your progress...