I saw these napkins made by Country Living (which I love) and knew I could make them. 
I used muslin for the fabric and bought crocheted doilies/lace at my local JoAnn craft store. 
I cut the muslin in 18 in. squares. For the off-white napkins, I matched the lace color and sewed it on about 3 in. from the bottom. Then I folded the edges under twice all the way around to make them neat. I found it's easier to sew them if you have ironed the folds down first.
For the white ones, I sewed the edges first, then positioned the doilies in the corner and sewed in a circle.
I also saw these easy napkin rings on Martha Stewart.
I used buttons with a shank on the back. I cut the satin ribbon to the size I wanted, putting both ends through the shank and tying a knot...and you're done! You place the ribbon under the napkin and wrap the loop around the button.(notice top pictures with them on the napkin)