You can follow any blogs that are hosted on blogspot. But how do you unfollow a blog, if you accidentally follow one?
I tried the suggestion here on unfollow a blog, but unfortunately the help seems outdated.
Click the "Settings" link for the blog you want to stop following. A new window will pop up asking you to sign on with either google or other options. Sign on by selecting google if you access blogspot through google. Enter your user ID and password. Your next screen you will see an option of "Stop following this site" link on the right side, near the middle of the page. After you click the link, you will need to confirm that you really want to stop following the blog.
On your Dashboard page, click on the gearwheel icon on the upper right of your Reading List near "View in Google Reader". When the "Manage Blogs I'm Following" page opens up, click on the "Settings" link across from the title of the blog that you want to stop following. A box will open so that you can log into "Google Friend Connect." Next, click on the "Settings" link again and a new window will open where you can click on the "Stop following this site" link. It will then ask you to confirm your choice or cancel it.