Don't tell me what you're going to do. Just do it.

Little is more annoying than a phone call informing you that someone is "just about to email" some vital information for an article. At least, it's annoying when you spend the next half hour (so far) waiting for the ping of said email.

It would have perhaps been more helpful for the source to email me the information and then call me to make sure I've received it.

Rant over. Just do it.