Oh, I'm thrilled to hear you'll be opening a shop! I always love to browse those and I'm sure you'll get plenty of requests, as shops are quite popular on PC, be it art or trading (or any other shops). n~n But hey there, Dark_Illusion, and welcome to the forum!
CSS definitely does make shops a whole lot more appealing, though it thankfully isn't too hard to do, yep. There's a wonderful CSS Help thread in Technology & Internet that Miss Doronjo has already linked you too; it's a great place to learn some of the basics and get a code going for your shop. :3 By the way, I really love the little popup in your signature that comes up when you hover over the text, it looks great and for some reason I can't stop hovering over it, hehe.
As others have said, you'll be on your way to meeting plenty of people assuming you stick around, so go ahead and make some more posts! Surely you don't plan on being at one posts forever, right? If you're ever looking for someone to talk to, my profile box is always open, though I'm always around to assist if you need help with the forum, too. Alternatively, you can contact Cid, the other New Users / Welcome moderator. :D
Enjoy your staaay~