The latest build is 8.0.20093.364. This was a 2009v3 release, so it would have been released in a setup around November 2009. You can download a zip file that contains the individual ocx files and a readme here: http://prerelease.componentone.com/activex/C1TrueDBGrid/2009-T3/TrueDBGrid8_8.0.20093.364.zip. The readme file will show all updates since 8.0.20024.294.
You can either install these files manually to evaluate, or install the entire 2011v2 ActiveX setup. The setup will install the readme files for all of the ActiveX controls. Many of our ActiveX controls have had more updates, so you should evaluate the whole studio if you are using any other controls.