As much as websites have gotten easier, there's still some things that you have to know how to do. Knowing HTML is a good place to start. Knowing how to compress images for web display is a good second skill. If you don't know either... Let's just say that you're driving on bald tires. You can probably go for a few hundred miles, but I'm not riding in the car with you. If your site is a blog and somebody else designed it for you, you can probably get by posting new articles, but if your site is more complicated - like a shopping cart, for instance - you're eventually going to need some backup. You really have two choices... Options for Running Your Own Website

1. Hire a Webmaster. Get someone on retainer that knows some web design, or at the very least some HTML and PhotoShop skill. When you get over your head (believe me, it will happen), you'll be glad you have someone you can call on. This can be your very knowledgeable nephew. I don't care. Just have somebody.
2. Start Getting Your Learn On. You have a long road ahead of you. Make sure you block out some time. You need to learn Photoshop (or an alternative program to compress images for web display) and you need to learn HTML. You can learn HTML in about a month with a good book. Photoshop is a bit easier to learn (at least for what you'll be doing), but the price tag is pretty hefty. $650, to be exact. Yes, yes, there are cheaper alternatives. You can investigate those. That will just take more research time.

What I'm really getting to here is simple. I assume if you're running your own website business, your time is money. I know mine is. Spending hours learning a new skill is hours that I'm not earning money. Now, if that skill will make me money, it might be a worthwhile endeavor. If it will only save me money, then it's probably not worth it. I'd much rather pay a guy to fix my car than learn how to fix it myself. I'd much rather pay a guy to do my accounting than figure it out myself. I'd much rather... well, you get the point.