In Firefox all you have to do is right-click and then click on "View Source". If you use Firebug for Firefox
then you can view the DOM (Document Object Model) in it's "HTML" tab which will also allow you to make changes immediately for testing purposes without having to reload the page.
Learning CSS3 should be considered more of a final touch, if you're just starting to learn CSS in general you really should establish a foundation from CSS level 1. You can read my CSS level 1 tutorial
which will save you from using CSS 2 position needlessly (which widely complicates styling when greenhorns try to brute-force with CSS) and then consider CSS3 after you've advanced your understanding properly.
I also recommend using XHTML 1.1 or XHTML 5 in conjunction with Firefox. Simply create an empty "example.xhtml" file on your desktop and open it with Firefox. You'll immediately get an error message which is actually good. When you're advanced like myself the last thing you want to do is waste three days trying to figure out a problem when you're simply missing a quote someplace. I have some [code=http://www.jabcreations.com/web/xhtml/]XHTML tutorials[/code] available that I recommend you read.
Instead of worry about a free web host right now you can actually run all your (X)HTML from your computer. If you really want to learn you can even setup a server on your computer so even without an internet connection you can use a programming language such as PHP and a database such as PostgreSQL even without an internet connection; I recommend XAMPP
which I use for local
I keep an eye on the forums on pretty much a daily basis so if you have questions I'll answer them when I get the chance.