Okay, so I've turned on trackback moderation to keep that from happening again. Still means I'll have to click "delete" hundreds of times, but at least they won't get anything out of it. I get so few legitimate trackbacks it's not a huge loss to have them have a delay before publishing.
Incidentally; die, spammers, die! You've proved you are antisocial cretins who just want to feed off the work of others, just do the world a favour and drop out of the gene pool.