This seems to be a new variation of the Amazon game:
I tried looking for Sonic Foundry software (got a $15 MIR form in the mail), and I tried it through mysimon.com and dealtime.com. I got the same products pulled up on both engines from computers4sure.com, but the products at mysimon.com were $2 higher(even with both windows open). It is possible that the site submits two different price lists to the two engines (dealtime had a cash-back program with this site), or it is possible one of the search engines is programmed differently. In defence of the store, they did have the lowest prices on the list (donot know if they would still have been the lowest after S/H).
Moral of the story: try various pricing search engines before deciding to buy a product

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