Here, I would like to share a few links which I generally use for learning Sitecore.
1. Learn Sitecore : http://learnsitecore.cmsuniverse.net/
This is not just for developers… Its for everyone; namely Developers, Editors,Architects, Administrators.
2. Sitecore Community : http://www.sitecore.net/Community/Technical-Blogs/All-Bloggers.aspx
If you want to either learn Sitecore or want to remain updated, you got to refer to this. These guys make it a point to share all knowledge in a short and sweet way.
3. Sitecore CMS Blog : http://sitecoreblog.alexshyba.com/
Purely Developer Stuff. Well, must say on this blog I saw lot of ideas to get solutions for problems while working on Sitecore CMS. He is one of the Community Technical Writers.
4. Sitecore Basics : http://sitecorebasics.wordpress.com/
Well, this is altogether a different kind of blog. Not only for Developers, but for many more. It contains many challenges or problems faced and solutions found or designed for them. Also, the way of writing is Simple and Effective.
These are the links which I refer to for any information on Sitecore. More links are always welcome!
Happy Sitecoring! 🙂