I work in transportation planning so I see aerials all the time. There are a myriad of great aerial sites out there and some are free. The resolution varies, but you can usually pick out lane lines and such. If it is in the US, search the county auditor's or the county engineer's website for their GIS data and look at the aerials.
Many times the linework data is saved in a dxf format as well, so you could bring in Edge of Pavement and building outines into Illustrator or some other vector program to create something.