So, you've got some decisions to make.
Adding duplicate content for the sake of just having "something" out there isn't going to help you in the long run. Look into the Panda updates from Google -- one of the things they don't want to see is duplicate content. The more of that you have, the more likely it becomes they're going to notice... and the more likely it becomes that you'll eventually get dinged.
(Beyond that, it's just not that interesting to your readers.)
So the first thing you've got to decide is why you have this website to start with. You say you don't even consider the site a part-time job, which sounds to me like you're not wanting to put all that much work into it. If that's the case, then maybe you should just stop worrying about it and let it die on its own. Find some other topic to write about that you find more interesting, or find some other hobby entirely. Not everyone has to have a website.
If you want to make something of it (or even maintain what it has now), you're going to have to put some work into it. You're going to have to make it into at least a part-time job. And that means coming up with unique, interesting, engaging new stuff to say.
If there truly is nothing new to say about the topic of your website, then I have to wonder why you thought it was worth creating a website on that topic in the first place? Even if your site is far-and-away the best resource ever on the topic today, it's bound to lose ground eventually as other, more enthusiastic webmasters come along and start creating terrific new content.
The other alternative is to find a good writer and pay them to create content for you. (And taking another look at the Panda updates, you'll see that crappy content isn't going to help you in the long run, either... so the operative term is: a GOOD writer. Really good writers aren't cheap.)