Was wondering if anyone could help me get an idea of how pricegrabber works...
 

How does it collect the different items and compare thier prices across different companies? Do companies manually add their items or is there some kind of spider like deal that pricegrabber uses to grab the items from the sites and then compare them?

I have a little idea brewing and have the coding skills to do it I just have got to understand how they make it works.

Any input is appreciated greatly.

my guess is probably a combination of both
the auto spider is ideal but it has to have a list of webpages that sell the items and some idea how to spider and some companies may give cash for it to spider. like the way yahoo does.

hmmmm

Does anyone know where I can find more info on this stuff? There has got to be something out there... It would be nice if I could see how they setup with the businesses to spider everything efficiently.

google spidering web pages there will be many programs written in various languages(programming) that can show you how spidering is done. its late here i just know its possable to do it but how to do it efficently is another story