There are a whole bunch of these stores selling OEM car parts: They
all display a custom front-end, designed to suit their marketing
pitch. At the bottom of them all, you'll see "Copyright 2009
Intelligentz Automotive Corporation". It seems like they all set a few
parameters: Mark-up percentage, shipping as a percent of total cost,
and minimum shipping, and that they all give them a custom look.
It seems that parts.com is the actual company's website (judging from
the whois record lookup of that domain), and its prices seem to be
lower than the link you cite. So, I'd check it out.
A dealer in my area has its shipping policy set at 5% of part cost
(compared to 15% for parts.com and hyundaipartsonline.com), so if you
were buying something expensive, it might be worth trying Drew
Hyundai's front-end to the system (or see if your dealer has a front-
end with similar settings).
It's sometimes hard to find the right part in their menus...