Here's the link to the NHTSA website where you can get one line summaries for every TSB - however, for some strange reason, the X3 is not listed among the available BMW models to view. Even if the X3 information were viewable, you would have to pay a fee to retrieve complete documents.

http://www-odi.nhtsa.dot.gov/cars/pr.../tsbsearch.cfm

Another source is www.alldata.com which is a subscription based information archival service dealing specifically with the automotive industry.

We should find a way to collect and reposit all TSB information on the front page. Does anyone know if this information is copyrighted?