I Need Help Making an Effecting Email Subject Line!!!

Hey Warriors!

I am looking for a bit of help with an email subject line. I know that a large amount of people will turn down an email based on what is within the subject line. I am currently targeting businesses that are looking to promote their social media management software, or social media marketing event. I have a LinkedIn group that has 4,300+ members and growing every day, so I figured it is a great venue for them to promote their software or event.

Here is the copy so that you can get an idea of what I am trying to sell these businesses.

"Hello _______,

I am ____________, the founder of the LinkedIn group "Social Media Marketers United". I would like to inform you that I am currently offering advertising opportunities for companies that are involved with social media management software, and events regarding social media marketing.

Social Media Marketers United
Currently the group has 4,382 members, and grows by at least 10-20 members each day. This group is a great place for you to market your software or event, since it consists of thousands of targeted members. You can visit my group by clicking here so that you can get a better feel of what our members are looking for.

I am currently offering two very affordable packages to help you promote your software or event to your targeted demographic. Below you can view each of the packages.


$100:
2 Emails - (1 email every 7 days. The email will be sent directly to each members inbox. You must supply the copy that you would like to be posted. Include any links and text that you would like for our members to visit.)

$200:
2 Emails - Supply copy for each email. The emails can contain anything you'd like, as long as it relates to social media marketing. (Include text and links that you would like for members to view.)
Hero Image - The "Hero" image, is the first image that members see when visiting the "Social Media Marketing United" page. You must supply the image that you would like displayed. (Dimensions: 646 x 200 & a maximum of 2 MB. Must be in PNG/JPEG/GIF format.)
Managers Choice Discussion - You will be able to post 1 discussion, that I will then put in the "Managers Choice" section at the top of the page. The discussion must be related to social media marketing, or about your software/event. (Helps increase views for your discussion.)
3 Tweets - I will personally send out 3 tweets at optimized times from my businesses Twitter profile @FrogSocialMedia. (My businesses Twitter profile has 6,000+ targeted followers.)

If you would like to set up a time to talk so that you can learn a bit more, you can email me at ____________. I would love to help your business in any way that I can!"


I just need help to create a subject line, so that they will open the email since I know most businesses inboxes are already flooded. Thanks for any help you can lend!!!

Also feel free to offer any suggestions about the copy above!