Did you configure it based on your site (second half of instructions, after installing)?

http://grohol.com/downloads/oj/latest/oj.cfg.txt

You have to tell the program where things are on your site and what things are named, it doesn't know who "you" are so has fake stuff and you have to fill in your actual, real stuff. Then, when that's all right I think you probably just ask for your journal by whatever name you gave it and it knows where/how to find all its stuff.