Go to the attached link.
Zoom in where you may want to or are able to fish. Like when fishing from a boat, look for points that will have moving water (Current
as Capt. Tom Hughes would put it) maybe with a back water area that could create a seam, like when trout fishing.
Click on the satellite as well as the topo, map view.
Between the two you can check out the land that surrounds the point for possible access to the shore and how the bottom contour may be within casting distance.
Topo view= water depths
Satellite view= sand bars, deeper water etc.
Click back and forth to confirm that the topo depths reflect the satellite view. This is only a starting point.
Just as Texas Tim said, all this takes time (homework) then comes the field exploration, walking, looking, etc, etc.
A short cut-
Spring, April, walk the bank from Lappidum to the Conowingo Dam, Harford county side. Lots of angler do this when fishing for shad.
Perry Point Park- there is a point at the top of the Flats. Not a big secret.
Kent Narrows- under the Rt 50 bridge. VERY swift current. Lots of bottom fishermen there. The place is all trashed up.
Just because you may not catch fish in an area that has all the criteria that is needed to hold fish does not mean that the place is no good. It may have to be fished several time at different times of the year, different times of the day with different tides (current). This could take years.
I hope I did not discourage you too much. It takes effort.
Or just go with a guide or find someone to go out with on their boat.
I'm in Harford County, I'll take you out.