How do you know there is no fermentation going on?
Are you brewing in a bucket, carboy, or stainless fermenter?
If glass you should be able to see fermentation occurring.
If plastic bucket, check to be sure that the lid is tightly pushed down (biggest culprit) and that there are no leaks.
Providing you had relatively fresh dry yeast packets, I would bet that your fermentation is well under way already. Don't be afraid to quickly open the fermenter and take a peek inside. Let us know what you observe!