Report for User contact information

Is it possible to run a report that returns all of the contact information for my users? We went through a merger a while back & there is inconsistency in how contact info (esp. phone numbers) was added (assuming that the information was ever added in the first place).

Of particular concern was a change in which fields were used for phone numbers. Originally Telephone Number was used for people's extensions, but now we have multiple offices with people on different phone systems (for now), so the extension is less important than their direct dials, so Telephone Number should be used for direct dials & IP Phone for extensions.

Unfortunately, I can't figure out a report that would actually give me a listing of the relevant information so I know what needs to be updated...

Is this even possible?

Tim King