Shortcovers is becoming one of my favorite bookstores: they keep having books I can't find elsewhere in ePub editions.
I haven't had any trouble finding my way around on their site but I admit that if it weren't for this thread I probably would not have gone back after my first visit. It wasn't clear to me from the site alone that they are a straight bookstore that sells ePub books for download to portable book readers as opposed to reading books on my computer screen, on-line only.