While a Google search for 'free stock photos' will find loads of links, they'll either go to sites that actually want payment or to sites which offer only a very small number of free images. That's unsurprising because people normally only contribute images to such sites in the expectation of payment if their images are used.
Unless you're planning to use the images for a massive advertising campaign (which seems unlikely given your zero budget!) the simplest option would be to (ahem!) 'borrow' some pictures from the web. Unless the images are marked as 'free of copyright' (or similar) you'll technically be breaching copyright but if, for example, you're only going to be using them to produce a local quiz sheet or a few personal greetings cards, the chances of you being sued are absolutely zero. (Even if the photographers were aware of your use of their images, most people wouldn't care as long as you weren't making money from them. Several pictures that I've put on the web have appeared, without my permission, on other people's web sites. I just regard it as a compliment to my photographic skills)
e.g. here's a 99 cone:
http://www.flickr.com...g/3836305330/sizes/l/
That's just one of dozens of images I found by using the Yahoo image search (which I find better than Google's image search facility):
http://uk.images.search.yahoo.com/images
(I searched for '99 flake'. Searching for '100s 1000s' also finds loads of suitable pictures).
Chris