Now is the time to take photographs.

There are definitely some books you can read that go beyond the technical basics. I highly recommended Michael Freeman's series The Photographer's Eye, The Photographer's Mind, and The Photographer's Vision.

But it sounds like you're mostly focusing on book learnin'. A book will never make you step up in your photographic skills without the practice to go along with it. It's really easy to read a lot of books and hang out on web sites without putting in the work — but putting in the work is what will produce the results. Malcom Gladwell, author of The Tipping Point, has an interesting theory that it takes roughly 10,000 hours of anything to become an expert. Put in time towards those hours.

As you take photographs, come back and take a look at the results with a critical eye. Think about what worked and what didn't. Choose your best few every month, even when it's hard to narrow things down. That self-critical process is a very effective tool. If you have two similar photographs that you can't choose between, make yourself choose one. Make some actual prints. Show people. (Don't get too hung up on web-forum "critique", though!) A local photography club might be useful, or it might not. The important thing is to make photographs, and to look at them. Don't get caught up in the secondary aspects (although you can do those too — that's basically what this site is).

Then, as you do that, you will come to specific things for which you realize you need to turn to expert advice and historical wisdom. That's when you look in a book, or ask a question here. You'll almost certainly discover that your understanding of even the basic concepts can go to whole new levels.