I think that just going out there and shooting away really is the way to learn. Put your camera onto AV setting for example. Go out and find something to photograph, maybe nothing more than a plant in the garden, and play with the aperture setting, learn what changing the aperture does to your picture. Try the TV setting on something that moves, again something as simple as water running slowly from a tap, change the shutter time and see how that affects your images.
If you want to learn, then going out is the best way to learn. But in my opinion, you'll not learn an awful lot unless you take the camera out of the auto modes. Perhaps look at composition, take the same picture with the same settings but with the main subject in different areas of the picture - Which looks better and why?
Have you looked at the tutorial section on TP - There's some great stuff to help you understand the relationships between the aperture, shutter speed and ISO. If you can get that cracked then you're well on the way to getting a good understanding.
Hope that helps.