Check Kijiji. You can find a lot of stuff on there for waaaaay cheaper than Racks Unltd. Thule boxes and rack attachments fit Yakima bars now (they're both round) so you can go back and forth. I have a yakima rack with the yakima skybox pro ($500 on Kijiji), and it's huge. You can easily fit 4 or 5 pairs of skis and boards in it, plus boots and and other odds and ends. I love it.
http://yakima.com/shop/cargo/cargo-boxes
If you're worried about fit get a new set up (rack attachments and crossbars only) at Racks Unltd (it's going to be $300-$400) but buy all the accessories on line somewhere to save some dough.
And yeah, get a fairing. The racks hum and it's super annoying on long trips (especially for dogs).