We know that blogging can be a very effective tool when used in the classroom. But, it can also be a great tool for developing your PLN. In fact, it's probably the easiest way to get started. You can easily find thousands of blogs relevant to your area of interest or expertise on the internet through a quick search using Googleblogs, Ask.com or Technorati.
Once you've found a blog, begin by reading some of the posts. The most current post will be on the first page you see. There is generally an area where you can navigate to previous blog postings (For instance, on the right hand side of this page you can access all blog postings from the past). Take a quick browse through to see if there are any titles or blog posts that interest you. You will quickly be able to judge whether or not that blog is a site that will be valuable for you.
Your next step should be to start contributing to the conversation. Topics and ideas presented on blogs will get you thinking. Ask questions, answer questions or tell others what you think. The whole idea is to have a conversation to deepen your understanding of a topic.
The final step is to create your own blog and express your beliefs and knowledge with others.
In the meantime, here are some of my favourites that deal with technology:
Free Technology for Teachers
My 2 Cents
ICT in Education
The Whiteboard Blog