It seems that company that sells those black tees (usually the vendors booths in the shopping mall) that have music band symbols on it, Jack Daniels, Thundercats, etc. are selling wu tang ones too with the yellow W like on the 36 chamber album.
I spotted several in the last month, and maybe coming close to as much as the Pink Floyd - Dark Side of the Moon black t-shirts with the prism.
Bookmarks