None of my nearby GameStops take preorders over the phone either, and some of the employees are definitely unaware of "web-in-store," so it may take a little persistence.
Knight, did you notice that's a new page for Shulk today? Here's the page he was sold on
yesterday, and here's the page from
today. With a release date 3 months out, this sounds like they're making more, and by the product image it's not a "version 2" reprint or anything it's exactly the same.
Bodes well for other scarce amiibos maybe?