This is how I started out and I would suggest it to anyone else who asks as well: Neopets! Your pet pages are coded in HTML and it's easy and fast to see results when you mess around with the code. I would also suggest keeping an eye out for Humble Bundle (humblebundle.com). They have PDF book bundles, and sometimes the books are about programming. A few weeks ago I bought a Python programming book bundle and it was a fantastic and cheap way to quickly learn the language.
I would definitely also suggest video learning sites, such as Pluralsight. It does have a monthly fee, but I remember a while back there was a way to get 3 months free (you'll have to do a bit of digging though--it wasn't easy to find). I just checked, and Pluralsight does have many HTML courses.