3 Ways to Diversify Your Network
First, find others who are involved with community groups that you are not. This shouldn't be your main reason for meeting with someone, but it's a good start to meet people who are not in your natural sphere.
Second, volunteer more. Find something that you like to do and see how you can get involved. Volunteering not only diversifies your network, but can benefit your community.
And finally, join the board of a local organization. It may not be as accessible as volunteering, but learn what it takes to join the board of a local business community group and take the necessary steps to commit.
If you want to build a powerful network, realize the value of diversity and branch out. You can find more networking tips in "Networking Like a Pro: Turning Contacts into Connections" by Ivan Misner and Brian Hilliard.