According to the game's FAQ page, fans will be able to order the digital Standard and the Digital Deluxe editions directly from NCsoft (Steam is not on the list, so they're out for digital pre-purchasing). These physical retailers, though, will offer at least the Standard and possibly the Collector's editions of the game, which means that fans will have a special interest in which of the listed retailers provide the CE version of the pre-purchase. Keep in mind that these are the retailers for pre-purchase, not necessarily launch or pre-order. The list is pretty lengthy; it's almost like ArenaNet wants to make pre-purchase as convenient as possible for as many fans as possible. Hit up the list if you want to figure out where you're headed on April 10th.