Hi Mike - Nice to see newcomers to this great application.
I suggest you download the skinning documentation, I'm not sure where it hides these days, but I would assume the downloads page would be a great place to start.
I've got a chm file on my site - http://www.xd.com.au which has dnn 2 & 3 solpart menu references, which haven't changed that much.
The default skins in the DNN release are a great place to start for now, but they use the nav menu which requires differen classes/techniques. (not much different but enough that you'll have to read up a little on it.)
You need to put a couple of different hats on - one being for site functionality - and this is handled on the site, eg.. page names, order, hierarchy.
The page name is done in the Page Settings when you add a page.
The page hiearchy is also done on the Page Settings but can be done when page is created AND edited later and put in a different place.
The page order is set dynamically - eg. when you make a page, it automatically falls in under the previous one. But you can move it by access the Admin / Pages tab and you can move, edit, preview and delete these pages quickly. It's handy to know this when you want to do those final 'tweaks'
Hope this helps you get started! 
Nina Meiers
My Site - My Blogs - Goodies - 28 Free DNNSkins - Nina's Free Skins