Yours look great. I found the bags in a scrappy magazine under utility bags. I've ajusted sizes to make cell phone cases, MP3 player cases,and of course my daughter's I-pad. If you make it a little larger than the reader, you can put a velcro slip inside to keep the pad or reader from slipping out and falling when the case is opened.
you can also use the pattern to make matching evening clutch bags.