You can filter all hubs with the dropdown menu on your left or search for a specific hub via the search box in the top right corner of your screen, but hubs are also grouped into subcategories. 

Hubs may appear in more than one category. Hubs are available for sell individually or as part of a custom wheel build. 

If you're ordering custom wheels, there's a checkbox at the bottom of each hub page that will allow you to add the hub to a wheel, and you'll be prompted to select spokes and nipples. After that all you'll need to do is find the rim(s) you'd like.

And of course if you have any questions about components for a custom wheel, call or email the shop.