Hi CAE. Welcome to SitePoint.
PayPal is by far the easiest option, and is very easy to use. You just past some simple code into your web page and presto, the user clicks it and is taken to PP and makes the purchase. The customer then gets an email from PP confirming the transaction, and you get notification of the same. Then it is up to you to fulfil the order. You are free to keep in touch with the customer by email or other contact details (if you have stipulated that they need to be included).
You could set up something like ZenCart, but it's a steep learning curve, and for one item, I certainly wouldn't bother. You also need things like SSL certificates, which are costly and tricky to set up right (unless you do this stuff every day).
A middle path is to sign up with a 3rd party service (like PP, but more sophisticated), of which there are many. They handle the transactions and provide some nicer reports etc than PP. There are many of them out there, but examples include [BigCartel, [URL="http://www.foxycart.com/"]foxycart, [URL="http://www.e-junkie.com/"]ejunkie and [URL="http://www.fastspring.com/"]FastSpring](http://bigcartel.com/) (for digital goods only) to name a few. These all provide you with buttons that you place on your site and which link to their own site (which you can style to look like your own) for payment purposes.
Another options again is to have your whole site hosted and managed by a 3rd party, examples of which include [Shopify and [URL="http://goodsie.com/"]Goodsie](http://www.shopify.com/). (Watch the Goodsie demo video at the bottom of the page. It's very cool.)