Reporting tool for Performance Monitor
I will point you to a reply on StackOverflow, regarding a very similar question.
PAL is very good. To use it:
Create a set of perfmon counters for each type of server (Web, SQL, App, etc...) you wish to monitor, customized to that specific server role. Export the counters as an HTML file, and import it on each server. Then run perfmon based on this file for several hours or days to capture a realistic workload on the server(s).
Then feed those raw logs to PAL, and it will provide a nice summary "traffic light" style report notifying you of problem areas.