Closer Ne-Yo Download 'Closer' on iTunes
Gary sent an online sweet shop into meltdown after a recommendation on Twitter.
The website of "A Quarter Of" was visited by at least 15,000 people within seconds of The X-Factor judge tweeting about them.
Owner Michael Parker said: "We had no idea what was going on."
The company, busy dealing with Christmas orders, was inundated with requests from some of Barlow’s 972,000 followers.
"There was a sudden massive flood of orders, which, on top of the Christmas orders, put a real strain on operations. But we’ve got great technology and a great team, so we just ploughed on until we got everything done."
The Take That singer, 40, whose Twitter name is @GBarlowOfficial, tweeted on Friday: "Check This Bag Of Goodies Out www.AQuarterOf.co.uk."
Owner Mr Parker added: "We always knew he was the judge with the best taste."