The second and third logos are my personal favorites. I like the way you incorporated the school book into the door of the barn for both designs, though I feel like the third one feels a little less cozy...
if your site is just html -- not php or .NET, you can simply make folders inside your root directory for each page you want.
for instance, if you have a 3 page site consiting of a homepage, an about page, and a contact page:
homepage is index.html in the root folder
there is an "about" folder in the root folder
inside of the "about" folder lives it's own "index.html"
this will make it so that it is www.yoururlhere.com/about
the same goes for /contact/ -- a folder inside of the main root folder named "contact" with it's own "index.html" inside of that.
if you are using PHP or .NET however, it is different. you can google search "php clean urls" or "asp.net clean urls" for more information on those, but here is a pretty comprehensive PHP clean urls tutorial using mod_rewrite: http://wettone.com/code/clean-urls