Flutterby™! : Nolo no go?

We want to order some books from Nolo Press, we get to put 'em in our "shopping cart", we go to checkout, and get "internal server error". Huh, kinda weird, but not unheard of, so we wait a day, try again. Same thing. So we wait longer, and try from several different machines. Same thing.

I'm not sure what they're doing wrong, but they're making it hard to buy their product. Charlene just called their phone number to do it the old fashioned way.