GAH - I just typed out my post, then sky broadband disconnected me when I hit 'Post' - well, here I go again...
I tried something similar to this once, you might find it easier to construct large apartment buildings rather than single houses to begin with. I'm not sure what kine of roads you'll want, but this is what I used:
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White = limestone blocks
Dark grey = diorite blocks
Light grey = granite blocks
They were made out of roads, but floor tiles should also work just fine.
If you wanted it to be REALLY modern, you could change the raws for various things, eg add concrete/tarmac, change wagons to lorries/trucks, update the weapons (battle axes are very rare in most cities, as far as I know).
Er, what else did I say...oh yes, I agree with RavingManiac about turning invaders off, will help a lot. And decreasing the pop cap might be useful, though that would mean less builders - it's up to you. Umm...I'm sure therre was something else.........ah - humans. You might want to play as humans instead of dwarves, but again - your choice.
I might join this later, but I can't be bothered right now...
I hate you, sky broadband...