You should be able to download it from the link provided in the benchmarking guide.
http://www.springsource.com/products/tc-server-evaluation
Although the name seems to have changed since the guide was last updated. I believe the correct package is : VMware vFabric tc Server. Grab the VMware vFabric tc Server 2.8.0 Standard Edition Runtime (Linux).
I should also point out that if you use the provided Linux templates, you can skip a lot of these steps as they've already been done for you.