I really have loved the customer service of this company:
http://www.paperandmore.com/They aren't all eco-related, but they do have some pretty recycled papers, and their vellum (transculent colored or white paper you use in invitations or programs) is naturally processed and recyclable.
They also have good "sample" options, where you can buy single samples or papers or envelopes (or even sample packs) and have them shipped to you for just a dollar.
I didn't use their cutting service, so I can't speak to that. But they can pre-cut your paper for a fairly small fee so you don't have to get out the x-acto blade yourself!