http://www.runoffgroove.com/articles.html take a look in here, quite a few possiblities but remember to match the impedence.
HTH
edit-I spell like a drunken monkey.
May I suggest the Testor decal paper..I had very good success printing a decal for a guitar with this but pretty much anything you print with an inkjet should work fine.
HTH,
Espy
http://www.decalgear.com/DG/Product.asp?ProdCode=62201
I've been lurking for years now and I registered just to post this for you Mashie: http://sonictronics.com/store/customer/product.php?productid=16350&cat=357&page=1
Hope this helps and I really enjoy seeing your work.