Shannon- Why do you want to blog? You say you want to be the only contributor- but are you talking about having a singular blog or a community conversation? The beyondmotherhood type of demographic should be talking to each other. Given the target market- you have plenty of job seekers and employers capable of providing information to each other.
Bob- How do you get the word out that you have a blog?
Getting the word out that you have a new blog is a rather basic process at the core
1- register with primary sources of traffic (Google, Technorati, MyBlogLog, Stumbleupon, and blog directories)
2- submit a PR announcement via the web (depending on the service, may get initial traction and readership going)
3- Post 2-5 pieces of content weekly for the first 2-3 months. (It is about quality and consistency, not being perfect.)
4- Converse on other like-minded blogs with intelligent commentary (do a search on topics via Google Blogs or Technorati), or simply search here on Biznik for members who have blogs that touch your topic.
5- Create an email signature via Feedburner (or similar)
6- Use social communities to spread the word about it (either online or offline), print some flyers with your latest articles or forward relevant pieces via your email list.