If you don't like the price of the commercial one, and couldn't be bothered to make your own....take the el cheapo way out.

Go to your local $ store, and buy a pack of balloons.

Paint on your white glue and water mixture where you are going to place the grass. Sprinkle on your static grass, let it set up for 5 mins or so. Blow up a balloon and tie a knot in the end. Rub the balloon on your head, (if you have no hair, borrow one of your kid's heads, wife/girlfriend's head, unsuspecting person walking down the street's head), then pass the balloon across the top of your work, the static charge on the balloon from rubbing it on your head will attract the static grass fibers, however because they are being held back by the glue mixture, they will stand up, and dry that way.