This is hard to answer not knowing your level of expertise with cameras and photography.
However, I can make a general statement. It is best to learn the camera and it's capabilities before adding on a lot of new accessories. I guess what I am meaning is to site with the manual and read it cover to cover. Then sit down with the camera and the manual and work through the manual with the camera, trying out every setting. This will get you very familiar with the camera in a relativly short amount of time. Once you have an understanding of the computer, I would recommend getting extra battery, more memory, external flash (a lot of people like the 420) and then a tripod.
I have the Canon Telephoto lens, and will be getting a wide angle lens as well, soon. I have looked at the raynox lenses and they appear very appetizing, especially with the lenses being threaded. The best advice I can give you is to read as much about them as you can. I do know that the Canon lenses are well made, and are a safe choice, especially since they were made for the G3. I will probably end up with the canon wide angle lens. Might get one of the raynox to experiment with.
Good luck.