Hi Dee Sa,
We were all beginners at some point so don't feel as though you are the only one. I bought a book called ebay UK edition in easy steps by Nick Vandome the ISBN number is 1-84078-286-2 (see if your local library can get it in for you, or see if they have any other similar books, there are a few on this subject). I read it through a few times, signed up with ebay and paypal and got started. It is quite easy. There are also question and answer forums (just like this one) where you type in a question if you get stuck on anything, and you get replies from other ebay members who help you.
The first thing you also need to do, is learn how to take a decent photo (by using your digital camera) of the item you want to sell and learn how to download the picture/s to your computer. Most people usually start by just listing up one item (say an unwanted book or item of clothing). Sell that, collect in the money and take it slowly. Don't start off by selling something really big and expensive. The easiest way to learn is to do it and gain experience as you go along. Just like using this site.