1. You can set up email subscriptions by using this guide > http://en.support.wordpress.com/widgets/follow-blog-widget/

2. If you would like a follow button to appear on the bottom right hand corner of your site for those who do not have WordPress.com accounts see here >
http://en.blog.wordpress.com/2011/09/21/more-traffic-for-your-blog-with-the-follow-button/

Social networking is strictly give to get. It takes months of posting frequently to attract viewers who will actually submit comments. The best way to get comments on your own posts is to leave meaningful comments on blogs with similar content to what's in your own blog. Set a goal of commenting on "X" number of blogs weekly and carry through.