Q: I accidentally removed my device from Icloud?

For what purpose?

How did you delete the device?

I removed a device, how do I add it back?

Once you remove a device, it will automatically be added again the next time the device connects to the Internet, as long as your iCloud membername and password are configured on the device under iCloud Settings > General. If this does not occur, see the "iPhone, iPad, Mac or iPod touch does not appear in Find My iPhone" section above. 

Above from:

http://support.apple.com/kb/TS4006

The same happened to me, IIIaass. Did you find a solution to your problem? Please let me know if you did!

This happens to me today to my macbook how can i track it now

The old fashioned way, you look for it. There is way to remotely track it.

But what if the device is stuck in activation. I still can't log in to remove the activation lock.

When you say "the device is stuck in activation" do you mean that it is asking for the ID and password last used in Settings>iCloud?

What happens when you try to log in? Log into what?

Are you the original purchaser of the iPod?

First, it's an ipad.

Second, No. I'm not the original purchaser of the ipad. I bought it from a friend and he removed his icloud id from the device. My icloud id is still on the device but i can't sign in. I went to icloud on my pc, trying to activate the my device. I accidentally deleted the my idevice from icloud instead of deleting it from find my iphone. Now i can't activate the **** thing.