There are a number of levels to photography you need to learn
1. Composition and subject -- what to shoot, how to think about what is in your viewfinder, etc.
2. How to photograph -- the basics on exposure, aperture, lighting, etc.
3. How to use a digital camera to take those photographs
4. How to post-process those photos for best effect (using Aperture, Photoshop, other tools).
There are tons of resources on line for #s 3 and 4. Here's one that addresses #3
http://www.cambridgeincolour.com/tutorials.htm. But without #s 1 and 2, you'll get well produced but perhaps poorly shot or boring pictures.
I'm not at my Mac, so I don't have my bookmarked links handy, but I know there are some really good sites for #2 and possibly #1. Here's a web page I just googled on composition:
http://www.picturecorrect.com/photographytips/composition.htm
A good site for talking to other G9 users is
http://photography-on-the.net/forum/index.php, though it's currently down for maintenance until 1700 GMT.
I used to take pictures with a film SLR about 20 years ago, so I'm just getting back into the hobby now. I've picked up some good books on composition, lighting and shooting at my local bookstore. I also dug out my old film SLR, and was playing around with it. Once I put it in my hands, I remembered how I used to use it (like riding a bike), then I picked up my G9, and transferred my old thought processes onto my new equipment. That helped a lot.
If you've never shot with an SLR camera before, and you want to get serious about photography, while the G9 is a very nice camera (IMO the best for what it is -- compact, full featured and RAW), you would probably learn better on a DSLR, because the range of settings is much greater on a DSLR, so you can see more dramatic impact on your images when you do things like change the Aperture. Of course, a DSLR is a problem to tote around.
Lastly, look for a local community photo club or photo class. A brief time in a class or with a group of photographers will get you off to a strong start, and then start shooting.