I tried looking on Google, but there are some fairly contradictory results.
I thought I’d ask you guys so we could get an authoritative answer on the subject!
COCA BNC zeros 312 132 zeroes.[n] 106 5
So in practice zeros is preferred in the US and even more so in the UK, though citations for zeroes include such prominent examples as Stephen Hawking’s Brief History of Time. (Mr Hawking is British, but the book was first published by an American publishing house.) The oldest citation for zeroes in the BNC is from 1978. The Corpus of Historical American English has six citations that are even older, the oldest one being from 1914.