By law all repair info and special tools must be available from anyone that wants to spend the money.
The only real trick is knowing what to buy and where to purchase it.
At this link you can download files for almost any automotive manufacturer selling cars in the US. We of course are interested in the BMW zip files. Inside them you will find descriptions of everything you are looking for and each file also contains contact info for the place to purchase the info/parts/CDs etc.
NOTE: At the link above the BMW files are not always listed. However if you look at the locations of the various files there and substitute bmw.zip and bmwnew.zip you will get the files.