Travy - I'm nowhere near being an expert, but do take a lot of macro shots - and never use a tripod ... I know that everyone says that it is best to, but to be honest, if I did, I'd never get a shot. The more you use your macro lens with your camera, the better you will be at taking the shot the instant it is in focus - it is more about technique in my opinion. And the more shots you take, the better you get.
An external flash makes a hell of a lot of difference, as the guys have said, the onboard flash doesn't make it over your lens, and you just end up with really harsh light, bad shadows and not the shot that you want. I use an SB800 with a PJ lightsphere - it gives a really good even light (in my opinion anyway), and while I had looked at getting a ring light, I'm actually really happy with the results I get with what I've got
I usually shoot with the flash set to full manual settings, camera at f22, and approximately 1/250 (depending on what I'm shooting) - and I seem to get reasonable shots

(I'm shooting with an old d70, 105 macro lens and sb800 flash).
One of the most important thing to think about when you are taking macro shots is the angle of the shot - if you can take a shot parallel to the subject (with most of the subject running in a parallel line to the focal plane) you'll have less issues with DOF....
By far THE most important thing though.... HAVE FUN
Just my 2c worth anyway.
(if you want to see some of my insect macro shots, so you can see what I mean, this is a link to my pbase account
http://www.pbase.com/narellepower/narel ... hotography
I'm not a great photographer, probably not even a very good photographer, but I have fun

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