Shadow Boxes?

[gemmedazure.livejournal.com]

Allo craftgrrls! :) *waves*

I'm currently working on a project which I've deemed "Portable Devotionals" - basically what they are are shadow boxes decorated elaborately to reflect varying dieties, elements, ideas, for people who haven't the space for a full-sized altar area or who would like to take a devotional with them when they travel. Thus far the "prototype" is coming along smashingly (the focus is Gaia), and I have having so much fun doing it. I'd like to do more but here's my dilemma:

I bought the shadow box ready-made at a sale, and it cost $10. That's not too too bad - but they're usually very hard to find and when you can find them they're crazily expensive. I've combed ebay and a few other crafty/decor sites but to no avail. Do any of you clever ladies know where I could get some fairly cheap or perhaps even better, how I could go about making my own without heavy toolery?

Thanks in advance!