What you are trying to do; which one can ascertain from the way you are doing, or the information you are looking for from others; is basically making out a survey or surveying the facilities, processes etc of others.
This is not "bench-marking"; and no wonder your boss is not very happy with it. It would be ideal, if you could sit with him and find out what exactly he wants to be 'benchmarked' - it can be anything from process to delivery, or facilities to resources.
Benchmarking is basically a process wherein you identify who is doing best in what way. One then pits oneself against that best practice or norm and make attempts to improve oneself to bring up to that level or better. For this one has to identify the best practice, rather than studying all the practices and process of all entities indulging in that activity.
By that what I mean is,you don't need to know or study the entire history of all the training institutes around you. Rather, you should identify the best performing unit in training; and then try to adopt or align your practices with that so that you achieve similar or far better results.
Hope the above is useful. Feel free to go through other comments, which will be added to this shortly and discuss further.
10th January 2013 From India, Delhi