Where can you find Insomniscope in Pokemon Mystery Dungeon?

Insomniscope is not an item in Pokemon Mystery Dungeon. There is no item with that name in any of the games in the series.

It's possible you are thinking of a different item or a similar-sounding one. Could you please provide more details about what you are looking for, such as:

* Which Pokemon Mystery Dungeon game are you playing?

* What is the effect you expect the item to have?

* Does the item have a specific appearance or name that you remember?

With more information, I can help you find the item you're looking for.