Meijer or WAL*MART.
I've had weird luck with WAL*MART and it's endeared itself to me that way. Like, times I've gone different places looking for something.... WAL*MART's the one that has it. Found great buttons for my Janet dress there, along with the fabric. Heck, I got my fabric for my Droog codpiece there after JoAnn's just had so-so options (I'm not a fan on JoAnn's at all, but I was looking for something rather simple).
I also like their site-to-store practice.