If you can make a card, you can make a bookmark. It's as simple as stamping your design and sandwiching a bit of ribbon between the designed piece and a piece of cardstock backing. All of my examples here are 2.5 x 6.75" in size (not counting the ribbon).
I used a variety of background techniques in my examples, but most of them involved smearing Distress Inks on my non-stick craft sheet and dabbing the paper in them. I also did a lot of sponging with Distress Inks.
Of course, you can get much more creative with the ribbon and festoon your bookmark with all kinds of fiber-y fun! I tend to lean toward not doing that because it's my personal taste - I don't like a lot of froofy stuff getting in my way when I'm hauling a book around and/or reading it.
Stamp set used: Blockheads Coffee Tea
I particularly love this last one. You could do a whole Day of Relaxation Basket - throw in a good book, a couple of CDs, some good coffee, a pretty mug, some cookies, and this bookmark. Now that's my idea of a great present!