Official home page:
http://www.trolltech.com/products/qt
Reference collection:
http://www.qiliang.net/qt/
Samples:
http://www.kdevelop.org/index.html?filename=users.html&set_lang=zh_CN
Building QT 4 with Visual C++ 2005
http://wiki.qgis.org/qgiswiki/Building_QT_4_with_Visual_C++_2005
