OneNote Evernote Importer - import source url
Sorry - there isn't an Importer section - so this is the closest I can find - but there seem to be a lot of Evernote users here...
When importing from Evernote - the OneNote Evernote Importer doesn't import the <source-url> field of the enex format and so you can't see where your notes originally came from (the oneNote clipper fortunately does do this - although its a shame it doesn't seem to be a meta field in OneNote and is just text appended to the end of a note?).
The importer really should do this and emulate what the clipper does.
Please consider this - for now I will have to painfully write something to do this myself, and update my .enex file.