1. Wrong forum. There is a TestDirector forum somewhere around here. Seek it out.
2. There is no downloadable trial version. If you are a viable purchaser of the software, then Mercury would consider giving you a limited trial version. Key words in the previous sentence: viable purchaser. That means that you would be willing to pay the funds upon determination that TestDirector meets your requirements.
3. Learning TestDirector? Your best option, barring finding employment in a company that uses the software, is to click on the Training link on the top of this page and review the TD training.
"The single biggest problem in communication is the illusion that it has taken place."
-George Bernard Shaw, Irish playwright and Nobel Prize winner, 1856-1950