As Bart Simpson would say: "while those are all moderately cool ideas," if you want to really find a website that saves you money on parts, check this one out:
I've been looking for new Denso ignition coils. Oddly, they are no longer even listed on rockauto.com. This Toyota dealer (Conicelli) in the Philly area has the second lowest price on Denso ignition coils, but their shipping is much lower. Moreover, if you check their Facebook page (no need to log on, just stalk it), Conicelli Autoplex seems to run 10% discounts just about every month. Sadly, their December one just ended but I'm pretty confident after scrolling down the Facebook page that another one will come in January. So with their price of $71.86 per coil, after the 10% off, it would be around $64 per; that's $5 below the lowest price I had previously seen ($69.89) from toyotaonlineparts.com. Also, if you happen to also own a Hyundai or Honda or Nissan, click on the Conicelli Autoplex tab at the upper right of the partznet link I provided above. On the next page, click on the partznet tab in the blue banner. That will now display the four auto makers' logos. Click on your car's manufacturer logo and begin searching for parts. If you click on the Toyota link you will see that they are offering free t-shirts for orders over $50.
I may be jumping the gun a bit, but my Vibe is approaching 110,000 miles, so I'm figuring it is getting close to needing fresh ignition coils. At these prices, I don't mind being proactive. Enjoy.