These are links that I like:

Jarek Szymanski's pages   are full of good research into Xinyi, Xingyi, Bagua, and Taiji.  If you like my site, you love this one. offers solid information on Nei Jia Kung Fu. More
specifically Jiang Rong Qiao's Bagua, Xingyi, Taiji, as well as Wu Style
Taijiquan and Ma Yueh Liang." Open Mind Designers IMA - A source of study and research in the field of  Internal Marial Arts.