Dennis, some of us fasten our buildings to scrap plexiglass rectangles painted gray to represent sidewalks.
I've see black or gray roofing materials cut into strips. Friends have also used those 2x8x16 landscaping pavers to represent streets. With the fake sidewalks sticking out over the edge they can be more convincing than it sounds.
Most of my towns come and go seasonally, so I just pour fine gravel where I want to represent streets. If you do that with crushed limestone, it may congeal enough to become fairly stable. (Unless you live in an acid rain state.)
For embedded trolley tracks, I know folks who have cast the track right into real concrete up to the top of the rails, then run something along the inside of the rails between the time it started to stiffen and the time it started to harden. I haven't done this myself, or seen a good example, but I'm told they exist.
Anyone else with other suggestions please respond. . . .