Yes, they'll work with the 40D.
I'd recommend the 100mm since it gives you more working distance, and it's reviewed as an amazing lens, very sharp and well built. AFAIK, the 60mm lens only does real macro (1:1) with an optional accessory. You might also want to look at the Sigma 105mm Macro lens, which has gotten some pretty great reviews as well.
After seeing many, many pics online, I'd personally go with the Canon 100mm macro.
I'd recommend the 100mm since it gives you more working distance, and it's reviewed as an amazing lens, very sharp and well built. AFAIK, the 60mm lens only does real macro (1:1) with an optional accessory.
My personal inclination is towards Canon rather than third party, because the Canon macro focuses internally; I understand (but I could be wrong) that the third party macros extend when focusing, which normally isn't a big deal, but on a macro, I think it is. Check before you buy.
Sweet! I was leaning more towards the 60mm lens, but since everyone is saying the 100mm, I think I'll check that one out.
The 60mm f/2.8 does do full 1:1 macro. It is the 50mm f/2.8 Macro that does not do full 1:1 out of the box.
Yes, they'll work with the 40D.