The new issue of Pragmatics & Cognition (2004, Volume 12, Issue 1) has a paper by Zohar Livnat: On verbal irony, meta-linguistic knowledge and echoic interpretation and a review of Adrian Pilkington's Poetic Effects: A Relevance Theory Perspective by Motti Benari.
You can get the papers online if you have access to a university subscription to Athens or one of those services. UCL has, luckily.
I've read the review of Pilkington's book and I think it shows some serious misunderstandings of relevance theory or Adrian Pilkington's interpretation of it. The introduction is really good though. I'll post some of my thoughts if I have time later.