Ruth Schmuff holds mystery classes throughout the year at her shop and encourages mail order participants. Once the class is finished, the canvases, threads and stitch guides are still available. Here is a list of the current classes with the "solved" mysteries listed at the bottom of the page.
Canvases are available from Raymond Crawford, HP Designs, and Melissa Shirley. Note that some canvases may be unobtainable from the designer in the future, so act now if you are interested in buying a kit from Ruth with one of her guides. As far as I know, the guides are not available separately.
UPDATE: Ruth has done a Melissa Shirley beetle purse for herself and has written a stitch guide in case anyone wants to stitch this for themselves. Here's her finished purse. Click on the title of the article to go to her shop website to buy the canvas. You'll have to email her about the stitch guide and threads separately.