Were can I find a rare pokemon?

You can find that on Route 2, Route 3 (With Dowsing Machine), Route 13, Route 16, Pinwheel Forest (With Dowsing Machine), Desert Resort (With Dowsing Machine), Nimbasa City, Mistralton Cave, Chargestone Cave, Twist Mountain (With Dowsing Machine), Icirrus City (Winter Only), Anville Town, Victory Road, Abundant Shrine, Lostlorn Forest, N's Castle.

Well as shinies afre rare here is a list of the games rarest Pokemon
Tornadus/ wanders around after you find it on the route to the Pokemon tower (must complete themain story first)
Landrous/ bring Tornadus and Thundrous (exclusive to white verion) to the abunt shrine and press A by the shrine itself (after the main story)
Resiram/ catch it at N's castle
Kyurem/ inside the cater the main outside Lunacous town after the main story
Zoroark/Zorua/ transfer an event Celibi anda gamestop/WIN2011 beast from a previous version and go to GAMEFREAK building for Zorua and Lostlorn forest for Zoroark
Victini/ get the liberty pass from wifi gift and head to the liberty garden from the boat in Castellia city
Tynmo/Dieno/Axew I'm listing these because they evolve in to Eelektross, Haxorus, and Hydregen witch can be caught at ChargeStone Cave (Tynamo) Victory Road (dieno) and fraxure th evolved form of axew can be caught there as well
You can get other rare Pokemon Here witch goes to the Pokemon trade forum here on supercheats where you can request any Pokemon and get results genuanly fast

You say hi then you get victini

There are lots of rare Pokemon in Pokemon black. Ive caught all of them but ill tell you which are rare and where to find them...

Cobalion -lvl 40
Cobalion can be obtained in the guidence chamber after you talk to an old man in I believe MIstralton cave. To get to Cobalion you need a Pokemon that can use surf, strength, and flash. BE prepared buy lots of ultrea balls and dusk balls.
Terrakion-lvl 40
Terrakion is obtained in victory road after you catch or defeat cobalion. Come prepared with dusk balls and ultra balls.
Virizion-lvl 40
Virizion is obtained in pinwheel forest(towards the east) after you catch or defeat Cobalion. Come prepared with ultra balls
Volcarona-lvl 70
Volcarona can be obtained in the desert resort when a team plasma member tries to obtain it. Come prepared with ultra balls.
Darmanitan(zen form)
Obtained at the destert resort. You know those weird statues in the desert resort? Those are darmanitan. You can only catch one after the professor gives you a rage candy bar.
Kyurem-lvl 70
Kyurem is caught in the giant chasm. He is VERY difficuly to catch so come prepared with lots of different kinds of poke balls

BLACK ONLY AND ONLY WHEN YOU TRY TO TO ROUTE 10 Want tornadus READ THIS! Go to route 7 or 8 (I think) and then go the second house you see. So then when you try to walk by a old lady would come out of the house and invite you in. Then when you get to come out and try to walk by the house AND THEN TORNADUS WILL APEAR AND THEN YOU GET TO BATTLE HIM (WARNING HE WILL FLEE AFTER YOUR MOVE) IF HE FLEES YOU WILL NEED TO GO TO ROUTE 4 OR 5 OR 16 ps use master ball

Go to wi-fi and get the liberty pass

This is for Pokemon black you can get the movies zekrom or get the apposite if yo have Pokemon white on mystery gift via wifi!

Well you can catch rare Pokemon in shaking bushes. And don't forget about the legendary Pokemon! They are not in the shaking bushes,though.

I know where to get genesect but I can't get him he is found in challengers cave (remember to try and click on rocks give it a try!)

What about Relicanth which can be found on route 4 down beside the fishermen. Relicanth appears in the black sports that pop up in the water then you just use the rod to "hook" relicanth.