The B-25 Mitchell was an effective light bomber and ground strafer, especially in the South Pacific and Burma, where variants were operated with a nose-mounted 75mm cannon and beaucoup .50 cals.
The RCAF reserve squadrons in Edmonton and Saskatoon flew them up until 1960-61. I remember seeing them around Saskatoon. They were a forgiving plane to fly.
You can see one at the USAF Museum at Wright-Patterson AFB in Dayton,OH. Other air museums in the US which I can recommend from personal experience include the Navy museum at Pensacola,FL, the Pima County Air Museum at Tucson,AZ, museums at McMinnville (they have the Spruce Goose) and Tillamook,OR, and of course, the Smithsonian in Washington, DC.
The Edmonton museum on Kingsway has a B-25 in process of restoration and I believe the Air Museum in Rockcliffe also has one. If you want to see lots of B-25 flying scenes watch the movie Catch 22 which was filmed in San Carlos, Mexico in 1969. I spent some time in San Carlos a couple of years ago and you can readily identify the mountain which appears in the movie.