I just got my Williams Sonoma catalog and was astounded to find peppermint bark selling for $24 a pound (or get two pounds on sale for $39) plus shipping.
Making your own is easy to do by yourself or with the kids and, trust me, tastes as good and costs a lot less than the catalog version.
Want to make it a more luxe? Use a high quality chocolate (maybe the See's semisweet chocolate chips I reviewed).
Here's link to the original post last year and the directions.