If you need a simple tip, I cheat the auto-focus on my digital camera by making it focus on my hand or thigh, first. Since the Premier I use only focuses on something that fills over 70% of the view, it's the only way for me. I set it to focus on my hand from, say, 2,5 inches, and then move it to the object I want to shoot.  Still difficult for very small objects but works for me most of the time. :-)

 

Liam