Best prices are not always found on the internet. However, many retail stores now match internet prices, and some even guarantee low price for 30 days.
I just recently looked for a new computer, and found a couple that looked good, an HP and a DELL.
I went to BestBuy to look at them, and told the sales rep I was interested in the DELL (23.8" screen, all in one) for $429 on sale from $500. He said a customer just returned one, and the open box one will sell for $330 with 11 months warranty, so that's the one I purchased.
I love it.