Nah, I would say that your first two paragraphs are too brief, and that you really do not need to provide any chart authors at this point in time. Perhaps consider sending:
"As I'm not an employee at Harmonix, I'm not in a position to make business negotiations. As a huge fan of both Testament and Rock Band, I only meant to inform you of the opportunity to join Rock Band Network. This is all my bad, because I really should have specified this in the first e-mail. I'm sorry if I caused any confusion.
However, if you wish to learn more about Rock Band Network or contact its developers, then please head over to their official website: http://creators.rockband.com/
Additional information can be found through the RBN Press Release: http://www.rockband.com/forums/showthread.php?t=152225
And, finally, the RB Support E-mail is at this address: [email protected]
Once again, I apologize for my mistake. But I really do hope that you're interested in RBN, because I (and so many others) would love to thrash through some Testament on Rock Band.
Hope this helps, Miss Management.
Of course, this is just my own opinion. I would recommend waiting to see what a few other forum-goers say before making a decision on what to send.