Ormston was born in Yorkshire, England and earned a degree in art and illustration at Leeds University in the mid 1980's. Ormston's dark, thick paints have graced the pages of 2000AD's 'Judge Dredd' strip on several occasions, most notably in the Judgement Day and Raptaur storylines. For Judge Dredd Megazine, Ormston also created the comedy strip 'Harke & Burr' with Si Spencer in 1993.
Ormston has been a regular on DC/Vertigo titles since 1995, starting with a contribution to 'Sandman Mystery Theatre' and 'The Sandman: The Kindly Ones'. He worked with Peter Milligan on 'The Eaters' (1995) and with Steven T. Seagle on two issues of 'House of Secrets' (1997-98). Among his best known works are 'Lucifer' (written by Mike Carey), 'The Girl Who Would Be Death' (written by Caitlin R. Kiernan, 1998-99) and 'Books of Magic: Life During Wartime' (written by Si Spencer and Steve Yeowell, 2005-06). Other works are 'Totems' (with Tom Preyer, 2000) and 'Northlanders' (with Brian Wood, 2008).
In addition, Ormston has done art for Dark Horse's 'Predator' comics, Kitchen Sink's 'The Crow: City of Angels' and on Image Comics's 'Todd McFarlane Presents: Ozzy Osbourne' (with Paul Jenkins).