What I learned from this type of photography from 2008 until now 2011 is... (note: the pic on the left was taken when i first got my camera. It came with the 17-55mm lens. Thats all i had at that time. The other pic was with the 100mm macro which took some learning to use right itself)
1. Center focusing or just changing the focus point of the camera to all over to pin point a certain area you want in focus
2. A macro lens is needed to get the type of details I like to see and obtain
3. Working with contrast
4. Noise reduction
5. Cropping Limitations
What I learned since the second picture taken a couple weeks ago...
1. No flash on something in bright light unless you are at the perfect angle to not have more than one light circle in the reflection of the eye. (5 years and 1001 days ago)