Get the 50 2.5 macro instead of the 50 1.8, much better quality glass. It's not fast though, but it is a true macro.
The 100 macro is nice, so is the 180 which is what I have. I'm old school and use extension tubes as well as a teleconverter on my tilt-shift lenses.
I only own the 45ts, 85L, 90ts, and the 180L macro. I can do most everything I need with those lenses and thats for advertising work.
Can we use existing work in this canon vs nikon photo contest?