Michael Kan said:
For macrophotography, you might want to invest in a light tent. There are a number of sellers on ebay. I think I got a collapsable tent with a couple of different backgrounds and 2 lights for like $40.
A light tent will give you broad, even lighting like a green screen. That's great for showing off the painting and detail in a controlled way.
I was more curious if anyone would be interested in shooting a more 'dramatic' setup?