I primarily use Summit Pro Shop, but I have a similar account at Jeg's.

As mentioned Summit's search engine is far superior to Jeg's.

I have had good customer service from both although I think Jeg's is a little faster.

For smaller purchases I often buy racecar parts from Amazon, the free Prime shipping often makes up for slightly higher prices.

Joel, I had the same issue on a set of W-9 heads from Summit but they resolved it very quickly.