I’m trying to make a little blog network that functions like wordpress.com, where I can create and admin multiple blogs with a single user (or share blogs between users).
I’ve tried to do that by simply following this guide, but when I tried to create a new site, it created another user with it.
How can I enable the my blogs function from wordpress.com on a custom installation?
If you create the new blog using your email address, it will be owned by your user. Because you are acting as the super admin, it assumes you are creating for a new user.
Not entirely sure what you mean about my blogs, but if you follow the steps above then the new blog will appear in the drop down admin bar when you are logged in and browsing any site / admin panel as on WP.com.