Your first stop on the quest for learning HTML and CSS should really be W3Schools, if you have never heard of this site then you are missing out on some great tutorials. At w3schools.com you will learn how to make a website. They offer free tutorials in all web development technologies.
Webdesigntuts+ is a blog made to house and showcase some of the best web design tutorials and articles around. They publish tutorials that not only produce great results and interfaces, but also explain the techniques behind them in a friendly, approachable manner.
Lynda.com offers a wide range of video-based tutorials that can teach you pretty much anything about web design, as well as pretty much everything else for a monthly fee. An authoritative source of web design training videos, you can get a taster by checking out its free tutorials.
Smashing Magazine is really a fantastic resource of tutorials on all aspects of web design. Similar to .Net magazine, the lessons are aimed at the intermediate to advanced end of the web design spectrum.
Quackit teaches beginners how to create websites. According to the website they start off slowly, teaching you the basics such as HTML and CSS. Then slowly they introduce you to more advanced topics so that you can add more features to your website.
Codecademy describes itself as the ‘easiest way to learn how to code’ and has established a great reputation for itself within the web design community. Codecademy is a team of hackers working hard to build a better way for anyone to teach, and learn, how to code. We’re determined to succeed in realizing our mission to turn a world of tech consumers into one of empowered builders.
Treehouse is a video-based service, where you can learn to build websites, create iPhone and Android apps, code with Ruby on Rails and PHP, or start a business. The extensive Treehouse library of step-by-step video courses and training exercises will give you a wide range of competitive, in-demand technology skills that will help you land your next dream job or build your startup idea. No experience? No problem!
In School of Webcraft you can earn badges backed by Mozilla, that highlight your technical and community skills to your friends, colleagues and potential employers. School of Webcraft Badges are easy to display on your personal website, online profiles, and CV and use the Open Badges framework, a way to record, track, and display your skills and knowledge across the web. The site offers a host of free web design training courses, including ones in CSS, PHP, and HTML. What’s great is that they also offer courses in Spanish.
What makes HTML Dog different to most other HTML guides and tutorials out there is its focus on best practices. “Web Standards” are at its heart, which, to cut a long story short, is all about using technologies, such as HTML and CSS, in the right way.
CSS-Tricks actually a blog run by web designer Chris Coyier. He covers the latest CSS techniques. Recently it has become immensely popular among professional web designers. What makes this site so great is that it is constantly updated source of tips, tutorials, and video lessons, best of all its Free.
30 Days to Learn HTML & CSS was created because they believe everyone has the right to learn how to build wonderful things on the web. The course is 100% free and always will be, no strings attached. It is instructed by veteran web developer and trainer Jeffrey Way, and brought to you by Tuts+ Premium.
Whether you want to learn how to build a simple web site or something as complex as your own search engine Udacity offers everything. With Udacity you can learn a whole bunch of new and interesting things, and best of all the training is absolutely free and is led by expert professors from Stanford and the University of Virginia.
About.com has tutorials and how to guides on pretty much everything from changing a tire to changing a diaper, and of course they also have a plethora of different tutorials and guidelines for learning HTML and CSS online for free.