Good place to start.

http://blogs.mu/

Here you can create your own free MU site.

I created singlemoms.
http://singlemoms.blogs.mu/

Then beneath that I created dating.
http://singlemoms.blogs.mu/dating/

And can create several more sub blogs.

There is nothing posted yet, just wanted to make sure signup was painless.

Bottom line, you can go here and create your own network of blogs, themed or not.

Kelvin