Where can I download the RTC Eclipse client

One answer

I would go to https://jazz.net and download the same version of RTC that your server is. If you want to do things simply, just download the Plain .zip Files version that you can just unzip to install. If you can get the Client for Eclipse 4.6.x it is better IMHO.
Here is the link for the Eclipse Plain .zip for RTC 6.0.6.1