Well, the client and server of my simulator are written in JavaScript, mostly, but there's also the usual HTML/CSS/jQuery, Node.js and socket.io in the backend, and a little bit of PHP in some places.
A TCG simulator is a pretty huge undertaking. You might want to practice with making some easier card games. Say, Solitaire - make a Web-based copy of that game that comes with Windows.
Your deck is going to be an array. There are a lot of ways to represent cards. You could number them 1 to 52 and store them as numbers, or you could use strings like "3h" "5d" "Kc".
To put cards wherever you want on the screen, you'll need to use CSS's "position:absolute". Read up on that if you're not familiar with it. You'll probably also want jQuery's "animate()" to animate them and make them fly around as you click on them.
I hope that's enough advice for you to get started. Feel free to ask me if you get stuck. Good luck!
Server-side is a good place to go next. PHP is what I learned (even before JavaScript) and it used to be the most popular, but it has lots of flaws. On the other hand, it's really easy to get into.
I honestly don't know what to recommend. Python and Django seem popular, as does Ruby on Rails. Choose what you like.
Pick a goal. Work towards that goal. Repeat. That's how you learn, really.
And make that goal feasible. I made a replay player before a simulator. That way, I could do the whole project one step at a time, and it turned out to be much better than trying to build a simulator from scratch.
