I have 2 of these.
http://tyrumas.com/pro1428892.html
I also use these really cheap LED book lights that can be found in the Dollar Tree.
As far as building a cityscape goes you can use almost any thing its really up to your imagination. Cardboard, Styrene, Styrofoam, Foamboard, Pink consruction foam, Wood/Basil wood, and Plaster all will work.
I think Im about to dabble into the styrene world.