Is it possible to generate a data dictionary for the solutions which have been already installed and have been customized ?
Yes - You can extract this information from the instance database and feed it into a leveled ODA to house your information.
Are there instructions anywhere on how to do this?
There are not. This is a custom process we developed and deployed.
Nice...was it quite a bit of work with SQL scripts to get the data to the point where you needed it to be?
Definitely. I would say we probably put 4-6 months into the project in total, but the results have been wonderful and well worth that effort.