I guess nothing beats prior establishing of good terms with that blogger, but I realize that that might not be possible in most cases.
Emailing a short, informational and friendly piece to that blogger (with a personal note) is probably the easiest bet. If the things you're pitching are good and already online, a tweet may also be enough.
I recently liked (and blogged) this advice here on that topic: http://blog.thegodfounder.com/post/6826152792/email-pitching...