Former Wolverhampton Wanderers and Coventry City youth who broke into the Sky Blues' first team before arriving at the Deeside Stadium in 2005/06 - making more than 20 WPL appearances and scoring three goals. His contract was cancelled by mutual consent after finding first-team opportunities limited the following season.

Gary signed for Caernarfon Town in November 2006 and, after a spell with Eastham, he returned to the Deeside Stadium in summer 2010 and was the Huws Gray Alliance Golden Boot winner in 2011 and 2012.

Gary was a prolific goalscorer for The Nomads in his time at Deeside, netting 96 goals in 115 (+15) appearances. Gary left The Nomads for Bangor City in 2012, but returned to the Deeside Stadium in September 2013. Following a 17 month spell back at Deeside, O'Toole left to sign for Conwy Borough.