How do you catch Spiritomb on Pokemon Ranger?

To get the Pokemon Spiritomb you need to get a odd Keystone. One can be obtained in Twinleaf Town. There is a little pond near the South part of it, you need to use your Item finder or Dousing Machine on your Watch thing.

After getting the Odd Keystone you need to head to Route 209. Past the Tower is a broken looking rock. Go up to it and click on it. It will ask you if you would like to insert the Odd Keystone, Say yes.

When you finsh that you need to go to the underground and talk to 32 people. You can talk to one friend or 32 different ones it really doesn't matter.When all 32 people are talked to go back to Route 209 and click on the broken rock thing which is called the Broken Tower. There Should Be a Spiritomb around Level 25.

Another way to get one is through GTS only if you have Wi-Fi, that's how I got mine.

Well I hopes this helps :)