Minted is an online stationery, art, and home goods company. Their print quality is very high, they provide what so far I've found to be the most customizable products, and the range of products and designs is dizzying.
I have a whole range of products for sale there, from calendars to photo holiday cards to fabric and home goods to kids' stationery to business cards.
Pingg is an e-card and e-invite company known for their modern, design-oriented assortment of cards and invitations.
I remember when I first discovered their website I was (a) completely happy to have a more stylish e-invite alternative and (b) wowed and amazed at the designers whose designs they licensed. Big names and great designers.
Formerly owned by HP, Snapfish has been around a looooong time now, and you may best know them as an online photo print shop - you upload your photos and can order prints. Easy peasy.
But they also sell a range of products you can use your photos with, and I have a large assortment of photo cards for sale at Snapfish.
While the designs are not as highly customizable as at Minted, the pricing is amazingly affordable.
It might possibly be every artist-slash-designer's dream to see their work on fabric and wrapping paper. Well, that's what Spoonflower does. They turn my pattern designs into really awesome fabric (and now wrapping paper, too!!).
It was so cool the first time I placed an order and got actual real fabric with my own designs on it. Fabric I could sew into things! MY fabric!
Truthfully, my assortment isn't that well developed yet, but I plan to add to the collection in early 2014.
One of the smaller-but-still-major-players in the stationery game, Expressionery has been around since 2005. They're backed by one of the largest printing companies in the US.
There's no easy way for me to link to my work for Expressionery so you're out of luck there! Sorry!