Download the latest version of QC 11 evaluation version from the hp site below.
Download Quality Center 11.00
Steps to Download:
1. Open the above link
2. Click on the "HP Quality Center 11.00 Evaluation"
3. Login/Register to HP with valid information.
5. Now you will be able to see list of download links
6. Download this
II.Software_HP_ALM_11.00_Windows_TC096_15000.z01 files to one folder and extract it
7. You have the setup to install the Quality Center 11 trail version :)
Let me know if you want more information...