How to create a summary report that contains other reports? I have 4 reports that I run for 8 different environments. Each report creates a graph from some usage tables. It's very simple SQL that creates a very simple graph.

The guy who used to do these manually took the results of each one of these reports and pasted them into a powerpoint doc. 

I have been able to get each one of these reports into report server so you just need need to click on the report and see the graph. I can set up subscriptions to send out these results with no problem either.

The problem is that I am sure the managers don't want 32 graphs coming their way. They want only one doc to see all the graphs.

Is there a way to put all these graphs on one report?
You can do this.  You can create a single report that has multiple data sources (one per environment).  Add the data sets required.  Recreate the graphs (you may be able to leverage some cut-and-paste).  In order to format them nicely, you will need to place the graphs into the cells of a matrix. 

You could also build a single report that links to other reports.

I realize this is a high-level description of how to do it - if you need further details, let me know.