defintiely check out trisha's notepad. sha has more mac shadows than anyone else here i think.
i like mac because they're moederately priced for department store makeup. and there are a TON of colors.
some greens are :
juxt - light shimmery green
sprout - a little darker than juxt
swimming - a little darker than sprout
humid - darkest of the grass green colors, but it is kind of dark.
forest green, green, and kelly green are nice mac pigments which are loose, very pigmented mac colors. you can get samples of pigments on ebay.