I've found that there is no one-stop-shopping place for discount bike parts. Everyone has standout sales, and you're wise to shop around. Even Ebay, which tends to have somewhat lower prices on most things--gets beat out on some items from time to time by online shops like Chainreactioncycles or PBK. Take a cue from your Mom--shop the sales.

To me, that's part of the fun of building or upgrading or stocking up on spare parts for a bike--although it's a bit frustrating to have to hit a lot of different places to get everything you want at the lowest price.

If they all took PayPal, I'd be pretty happy.