I think that Fabricworm was one of the first online fabric shops I shopped from some years ago. They are still one of my favorite go-to sources for unique prints, including a great variety of Japanese imports. I have bought lots of fun, kitschy prints imported from Japan through Fabricworm over the years.
The shop is so well organized and easy to navigate. Not only do they stock a huge variety of quilter’s cottons (including a large selection of organic cottons) but they also stock a great selection of knits, voiles, courderoys, flannels and canvas. You can find links to the different varieties of fabrics here.
I’m also a fan of their collection of Birch fabrics. So many whimsical but classy collections. Their booth is always one of my favorites at Quilt Market.