The file download is available here. Once downloaded, you can extract it out to any location. It is used through the java command as explained at this site and here as well.
To get it running as soon as possible, run TCPProxy and set the browser proxy to the port 8001. The proxy will record the actions you take through the browser. Once complete, close the proxy and start the console. Create a grinder.properties from the example given and start the agent. Use the console to start the processes and stop it when you have had enough.
The results obtained are mostly time statistics. One would have to create or edit a script to obtain more specific details. Testing against a local webapp using Tomcat revealed a Java heap memory exception in the Tomcat logs. Against the same webapp on a public server, there was no errors in the Grinder logs.