If you get a 100mm macro, which I use exclusively when using the Canon 40D, you will need a ring light to give soft, even illumination of your subject. It fits onto the end of the lens, and you shoot through it. A normal flash is much too harsh for flower photography, especially when you have a flower with waxy petals.
The majority of my macro work is done on my Olympus FE120 point n shoot using available light, with the camera on a tripod and set to Self Timer to eliminate camera shake.
Before Xmas I offered to help someone with this technique, but have forgotten who it was as I was laid up with sciatica again for 4 weeks and was zonked out with meds and the memory suffered a little during this time.

Whoever it was please PM me and we'll get on with the lessons...... sorry.
Koshki, if you want to see examples of what I have done on the Olympus let me know. A camera is only as good as it's operator.
BTW, good pikkies Mike.