Is there any preffered material outside about magento theme development?

Is there any preffered material outside about magento theme development?

References

Reference NO 1

http://www.siteground.com/tutorials/blog/

Reference NO 2

http://themeforest.net/item/fortis-flexible-magento-theme/discussion/1744309?page=85

Reference NO 3

http://www.sitepoint.com/the-world-of-ecommerce-solutions-simplified-for-your-business/

Reference NO 4

http://www.amazon.com/Magento-PHP-Developers-Guide-ebook/dp/B00C7KFKP6

Reference NO 5

http://online.wsj.com/public/page/news-business-us.html

Reference NO 6

http://www.media-server.com/m/p/3ihbciv6

Reference NO 7

http://www.packtpub.com/article/adding-interactive-course-material-moodle-1.9-part3

Reference NO 8

http://www.pkhanson.com/