Welcome to the forums,
I am a fan of a few bands on Facebook and they all have created a group page or business page and send out updates rather than e-mails to the people that are fans of the their band.
They also have applications on their page so you can hear some of their demo's so you can decide if its your type of sound and then become their fan.
One of the biggest turn off's in Facebook, business and anything online is getting spammed by people, you can never really tell their motives and it gives a really bad 1st impression.
I think you would find your tactics would generate very few new fans and you'd be better off using your time networking and getting your Facebook page looking and sounding amazing, so that when you get some new visits they'll be more likely to become fans.
Also try and get some decent content other than speaking about the band all the time, things like quizzes, reviews, information. This will generate interest and help introduce your band to new fans.
I haven't seen your page, so please only take this as general advise!
Think about how you re-act to spam e-mail you receive?!? Most of it is blocked or deleted right, then most of the e-mail you send will meet the same fate!
Put your energy to better use and become your fans source of knowledge, you'll find it will be better for you and your band in the long run.