What are all the key items in Pokemon black 2, and how do you get them?

Question

besides the most obvious ones like the bike and such

Answer 1

• Bicycle: from man in the pier when you enter Castelia City
• Dark Stone: From N after you defeat him in N's Castle
• Dowsing Machine: Bianca gives it to you at Castelia Gate
• Gracidea: From Striaton city Pokemon center after showing a fateful encounter shaymin
• Pal Pad: obtained from beginning
• Prop Case: obtained from man in musical hall
• Super Rod: obtained from Cedric Juniper in Nuvema Town
• Town Map: obtained from Hughs sister
• VS recorder: obtained from Nate/Rosa after double battle in front of Battle subway
• Xtransceiver: in bag at beginning
• Colress machine: obtained from colress in front of terrakion
• DNA splicer: dropped by kyurem after battle
• Dropped item: nimbasa city by pikachu balloon
• Grubby Hanky: Cafe warehouse
• Lunar Wing: from strange house in top and center room
• Magma Stone: route 18
• Medal Box: Flocessy town after defeating two school kids in alder's house
• Oval Charm: from proffessor Juniper after completing unova dex
• Permit: From professor juniper after seeing every Pokemon in new unova dex
• Plasma Card: plasma frigate
• Reveal Glass: abundant shrine after showing landorus-therain form
• shiny charm: professor juniper after completing national dex

Note: I included all key items because I didnt know to what extent you meant by obvious ones.

Source: http://bulbapedia.bulbagarden.net/wiki/List_of_key_items_in_Generation_V