POST DELETED! You can't download winrunner now as mercury does not support it any more and there is no trial version that is available.
Re: download Winrunner
Free trial version of WinRunner 8.2:
In the US, please call 1-800-TEST-911 and ask to be transferred to the CSD team.
For outside of the US, please contact the sales department for your region and you will be put in contact with the appropriate person.
Check this link