You might want to post this on the Collaboration/Beta Testing forum. That is the appropriate place for a question like this.
If you email a forum member uninvited, they may well be hostile, and this will give a negative opinion of your product regardless of how good it is. Indeed, you may find that some of the members you want to contact have disabled email notifications.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
I'm with Pete on this one, Collaboration is the place for this. However, if you want my opinion then I'll happily give it a kick.
Panic, Chaos, Destruction. My work here is done.
Drink. Get drunk. Fall over - P O'H
OK, I will win to day or my name isn't Ethel Crudacre! - DDEthel Crudacre
I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer
Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett