TireRack is great, but I live near a warehouse, so I pick them up and avoid shipping cost. I save big-time. But only on the “high-dollar” tires. I have 10 cars and buy cheap crap on the “high-milage, rough-use” vehicles and use TireRack for the “good” cars that need quality, high-performance tires. Those are what you save the big money on by using TireRack, in my experience.
If you just drive a “normal” car and don’t need anything special, often the local franchise (Big-O, TiresPlus, Schwab or whatever is in your neck o’the woods) will have a deal on thier brand tire, with installation that is cheaper or just as cheap and easier than messing around with TireRack.
Whatever you do, DO NOT BUY TIRES AT THE CAR DEALER!
My advice: Use TireRack (or other internet site) to price compare the name-brand tires. Call the local joints and see how competitive they are on the exact same tire. This gives you a sort of “base line”.
If you don’t need/value/afford name-brand (and they are not always better than franchise brand) check out what the local guys have and go for it.
In my experience, the more expensive the tire needed, the more you (or I) save by shopping on the internet (but remember, I don’t pay shipping, I can pick them up from the warehouse). For inexpensive utilitarian tires, the local guys are competitive. I live in the Pacific area where Les Schwab in the King of Cheap Tires and can cut an impressive deal.
So, what do you drive? How do you drive it? Where do you drive it (highway or city? Rain or snow?) What is your budget?
Hope I’ve helped.
Edit: One more thing, I’ve had nothing but positive experience with Kuhmo tires for both value and performance. I have them on 3 vechicles (ranging from crap to performance) and they have all done well for the money.