How can I view someone’s Will?

Several times each year my phone rings and someone asks me how they can locate and view the Will of someone close to them.
The circumstances of these requests vary, but can be broken down into two main groups: Someone has recently died, and their relative wants to know if they are a beneficiary; or an elderly person is becoming forgetful and their relative is concerned that they have been coerced into changing their Will, and want to satisfy their curiosity.