Well, it sounds to me like you're starting off pretty well for yourself Misteddreamrose. One of the best way's I've found to learn and study the cards, is to start off with the traditional meanings given in the book, study the card, see what symbols relate to those meanings, and apply them to real-life people. You can think "oh, I see how this would apply to this situation in my life", or in some situation in your past, or something going on in a friend's life. You can then expand out from there, adding variations and alterations of those traditional meanings, and how other things that are pictured on the card relate to different, or even opposite meanings.
Take The Devil as an example: In many decks, such as the Rider-Waite, it pictures 2 figures chained by the neck - but the chains are loose, they could be easily removed if the figures wanted to remove them. While in others (such as the Karma Tarot I just got), the chains are tighter and would be difficult for them to remove on their own. The difference could be, just how willing of a participant in the behavior or "addiction". Would they be able to stop on their own if they so choose? That's just one very tiny example of the kinds of things to watch for between decks.
I love studying the Tarot, and it seems that every reading I do is as much a learning experience for me as it is for the client. I would make one suggestion though. Pick one of your decks (I would suggest either the Steampunk or the Gilded) and work all the way through it, studying the cards and doing readings for a while. Get pretty familiar with that one deck, where it's easier to do readings, or just look at the cards and think of a key phrase relating to it. Then start studying the new deck in earnest as well. Trying to learn 2 or 3 decks at the same time when you're starting may be a bit confusing and slow down the learning process.
When you do pick up that second deck, you'll probably start seeing that there are more similarities between that and the other deck than there are differences. This is a good thing, because the similarities give you a great starting point for learning the new deck and the differences and nuances it holds.
On the other hand, if you see another deck that really reaches out and grabs you ... add it to your collection! You can always come to it when you're at the right place in your studies.
