These languages especially HTML5 and CSS3 are easy to learn, and there's plenty of free training available on internet. Besides w3schools and Codeacademy I found these sites most useful.
learn.shayhowe.com - It is a simple and a more detailed guide on HTML and CSS. Once beginner course is completed, you can move to advanced level. Highly recommended.
Mozilla Webmaker - It creates an interactive environment which lets you create webapps within minutes. Moreover it is fun to work on website especially playing with X-ray Goggles.
Channel9 - It is a video blog by Microsoft employees. It contains lots of free videos on programming and Microsoft services. The 21 episode series that teaches fundamentals of HTML5 and CSS3 is absolutely free.
TutsPlus - You can get a huge collection of articles categorized under different sections. Most of the implementations are freely downloadable.
Sitepoint - An absolute beginner's guide, HTML5Rocks, TutorialZine and 9lessons.info are also best websites to learn and practice these languages.