British Armed forces doctrinal and training manuals are not available outside of the military because they are classified "Restricted".
The force reconnaissance role in the British Army is carried out by five Formation Reconnaissance Regiments. These regiments use the light Combat Vehicle Reconnaissance(Tracked) and normally come under the command of Div HQ. MBT's are not used in the reconnaissance role within the British Army.
There some excellent publications available that might help you understand how the British Army is structured and operates. Two that I would recommend are The British Army a Pocket guide by Charles Heyman. This book is updated every year and is a really good source of information on orbts and equipment. The other is 16 Air Assault Brigade by Tim Ripley, this book details the formation, orbat and operations of 16 air Assault. Both these books are available from Amazon.
I would also recommend the British Army web site
www.army.mod.uk as another good source of information.