I have created a page about the repaving project in Annapolis with several pictures.
What I failed to mention on the page is that when the WB&A started running the interurbans through the streets the city of Annapolis demanded that they provide a city trolley that ran no less frequently than every 15 minutes to accomodate local passengers, much like the "Jolly Trolleys" of today - buses built to resemble the old streetcars inside and out.
The link to my page is http://www.navpooh.com/street_tracks_1.html
, but I'm in the process of updating the page to add a photograph of track uncovered during a reconstruction project at Gate 1 of the United States Naval Academy in the spring of 1982, along with a short story about how I came to possess a slice of the girder rail (which I obviously still have) that was uncovered at the time. I am also adding photos of the last train to ever run over the WB&A tracks (you won't believe when it was) and another secret.
Regarding the powerhouse in Annapolis, it is indeed still there; it's an annex to the Leowes hotel. If you go to Bing maps, search for 124 West Street, Annapolis MD, and go to bird's eye view, you will be taken to an old fire station; the powerhouse - a trapezoid-shaped structure - is directly behind that building. The angle of the rear wall follows the old right-of-way.
Two substations are also still in existence - Jones and Jones number 2. Search for Jones Station Road, Severna Park, MD and go to bird's eye view, then go to the intersection of Jones Station Road and Baltimore-Annapolis Boulevard. Turn the map once clockwise and you will see: a white rectangular building with a door and two windows; this is Jones. Move the map toward the lower left-hand corner of your screen until Jones is just gone, then look at the center of the screen; there is the remaining bit of passing siding. Once more move the map to the lower left, but follow the bike path and you will see a building that is partially brick and partially concrete block painted red; this is Jones number 2.
Jones number 2 was built in 1913 as part of the Annapolis Short Line's conversion to 1200V DC; it was fed electricity from the Westport (Baltimore) plant of the Consolidated Gas Electric Light & Power Company of Baltimore. After the February 1921 acquisition of the Short Line by the WB&A the power distribution of both lines were merged and Jones number 2 was dismantled. However, after the WB&A went belly-up in August 1935, the new Baltimore and Annapolis Railroad (running on the former Short Line's tracks) was without power from Annapolis; they needed another substation. The answer was the reopening of Jones number 2. However, the equipment to be used at J2 was too big for the existing 45' x 30' building; the solution was the concrete block annex. (Information about Jones number 2 is from "Every hour on the hour" by John E. Merreken, Bulletin 130, Central Electric Railfans' Association, LeRoy O. King Jr., Dallas, TX)
As to remaining trackage, there are bits and pieces of track all along the old line. As someone already pointed out, there is a section of a passing siding remaining beside the B&A bike trail at Jones Station Road; there is another section in the median strip of Route 100 just east of the B&A bike path overpass; the last one of which I am aware is along the south side of Route 32 just as the NSA employee driveway ramp almost touches Route 32;visible on Bing bird's eye view, it curves to the left toward the road.
Hope some of this helps