So you asked for it
Um; about 20 or so hours overall, colours done in Photoshop CS3.
Feel free to ask questions, I'll try to answer them.
Final piece is up here
along with a couple of others.
NB this isn't a tutorial as such; i worked out a pretty solid method while working on these illustrations (I ended up producing more than 20 of them) but I've since changed my process a fair bit and always continue to experiment, but either way I hope it's helpful.
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