Hi...There are several different spray-in products you can buy for extensions. If you want to buy them quickly you can go to a salon near you that does extensions, and I don't think they'd mind if you've bought the extensions elsewhere, they would still sell you a spray.
There are a couple of spray-in products on ebay...Balmain Radiance Shine Spray at �8.95 and a Daily Spray-in for Hair extensions at �2.99. You may need to trim the ends though, if they are really frazzled.