Here is a few article sites that I like: http://marketing-a-website.blogspot.com/2009/06/article-marketing-tips.html
Why do you want to use software for submissions? Are you going to tell your customers you are doing these submissions with a software? Or you will continue to tell them you are doing this manually. On top of that you want this for free..
I think you should take a look at what you are asking and then think about how realistic your expectations are. In other words, it's just not going to happen.
I know it's my website, but we have a lot of great information when it comes to backlinking, article marketing, and social media marketing. fastwebstrategies.com help.