These are the books by Eoin Colfer that are reviewed on this site:
Dangerous fairies, might grant your wish, might blast you away with a biobomb. Depends how they feel . . .
Fairies need Artemis. Artemis needs fairies. Fair exchange, no robbery. Tricky situation though.
'We, Cosmo Hill, are the world's only Supernaturalists.'
Cosmo grinned weakly. 'What? You don't like clothes?'
'That's naturists, Cosmo. And nobody does that any more, not with the ozone layer spread thinner than cling film. We call ourselves Supernaturalists because we hunt supernatural creatures.'
More improbable doings from Artemis Fowl and his fairy friend, Holly Short.