Minijunkie has just posted an excellent painting tutorial, this time showing you how to paint a horde of zombies.
First though, a word about the mindset I employ when painting large units of zombies or other creatures (like Skaven). My approach is basically to go for an effect that looks cool as a total unit, rather than spend a lot of time on each figure individually. It’s just not efficient to paint these guys individually and worry about blending and highlights. Plus – they are zombies! They should look messy and gross (but “purposefully” so – not just a giant mess of colors). I should also mention an airbrush helps immensely although in this case I only used it for the priming stage.