I started writing c lessons for absoulute begginers but to advanced users, I think material can be considered quality, and my students learn programming with this stuff. If you wish feel free to start reading it here:

www.visualcmaniac.com

its only 5 lessons for now so maybe could be easier for you to start following it now in the beginning. Hope I helped..materials will be published on daily base. Enjoy now, or later when I reach more advanced topics... If you think this might help others, feel free to direct them to my url.

I think my blogsite would also prove to be useful for beginners.
http://learning-computer-programming.blogspot.com