I just converted a Desk Size Planner "folio" into a cover for my Jetbook Lite.
Other than having to cut out an area for the AA battery bulge to fit through it was a very simple project.
I found the "Mead Padfolio" at a local discount store (Big Lots) for $4.00. It is nicely padded and has a firm clasp as well which is nice in case things take a tumble.
Note: You'll notice that my reader is mounted low and to the right versus a more aesthetically pleasing centered. This is to facilitate getting my fingers on the page turn button (right arrow) in the scroll wheel in a comfortable manner. It also leaves room for a cliplight up top as well. I also made sure to mount my Velcro on the reader where my fingers would not have to rest on it when holding the device when it was not mounted to the cover as I don't think that would be a very pleasing experience. (even as wonderful as Velcro is!) Also I made sure to place the "softer" velcro on the reader and put that scratchy, nasty "hook" piece on the cover. Bottom line - if you opt to make a cover for yourself then "play a round" for a while to get things positioned properly for your own fit.
I found a sheet of very inexpensive black felt (89 cents) with adhesive backing at a fabric store that I cut into strips and placed around the rectangular opening that I cut out for the battery bulge. This gives things a nice finished seam or binding appearance and holds the inner/outer cover material together instead of just flopping loose and likely fraying over time.
My grandmother's influence from early on pretty effectively prevents me from treating myself to a $40.00 fancy leather cover. She constantly recited this ditty to all within earshot in her soft Scottish brogue,
"Use it up.
Wear it out.
Make it do or,
do without."