Rating the bus tour from dxf. Extremely knowledgeable tour guides, I felt like they must have a background in urban planning because they knew so much detail about every little community. Did a downtown sweep hitting some historic Detroit buildings and a stop at the shinola for the hipsters in us. Felt at times like I was getting the hard sell for Detroit, but worth it for all the interesting tidbits of Detroit lore.
d:hive is AWESOME! I have several lists of downtown attractions from them, and their tours of Detroit are out of this world.