[3] O'Leary's novels and poetry explore his Māori (Te Arawa)– Irish Catholic heritage.
His latest novel is Magic Alex's Revenge (2009), the third in 'The Dreamlander Express' trilogy comprising Unlevel Crossings (2002) and Straight (1985).
His works include Surrogate Children (poems, 1981), Ten Sonnets (1985), Out of It (satirical novel, 1987), Before and After (1987), Livin’ ina Aucklan’ (1988) and The Irish Annals of New Zealand (1991).
Under the Earl of Seacliff Art Workshop imprint he has published work by a range of writers, both alternative and mainstream, including: Raewyn Alexander, Colin Lloyd Amery, Sandra Bell, John Pule, Greg O'Brien, David Eggleton, Pat Bellaney, Jeanne Bernhardt, Tony Beyer, Ken Bolton, Richard Burns, Karen Peterson Butterworth, Meg Campbell, Rosalie Carey, Frances Cherry, Jill Chan, John Daubé, Rosalind Derby, Robin Fry, Basim Furat, Brian C. Hare, Heather McPherson, Isa Moynihan, Peter Olds, Victor O'Leary, Glynn Parker, Alistair Paterson, Mark Pirie, Vivienne Plumb, Ralph Proops, Gemma Rowsell, Brian E. Turner, Nelson Wattie, Adam Wiedemann and others.
In 2011, O'Leary collaborated with several musicians to produce an album entitled Fences Fall – Songs from the Lyrics of Michael O’Leary.