White ones here:
http://logicpic.com/HEX.HTM#1/2Drum
Silver ones here (shipped from Buffalo, NY--not too bad--I've ordered from them).
https://creativecutters.sslpowered.com/index.php?option=com_simpleshop&Itemid=42&catid=33&task=browse&limit=10&limitstart=20
I now usually cut my own from 1/2 inch foamcore.
HTH
Rae
I had this same problem for a wedding I did last week. Those hexagons are very hard to find! I had plenty of round boards, so I just traced the bottom of the pans onto the round boards & cut them out myself. It was a lot easier than I thought it would be & much cheaper than ordering the pre-made ones.
It's easier to just buy 1/2" foamcore from the craft store, and use an exacto knife to cut it yourself... At least, I think so 
I also use the foam board. Place your pan, rim side down on the board and trace then cut out. it will be slightly larger than the cake. If you need a thicker board just hot glue two boards together. you can cover and hot glue a ribbon around.
There is a website I found that has a few different shaped cake boards, hexagon is one of the shapes. They also have a butterfly shape that I have used for my neice's birthday, it's pretty cool because I don't have to go buy expensive cake pans! The website is uniquecakeboards.com
Rae,
that logicpic.com website you posted requires a user name and password to get into the site...I have bought from them before and never had to have that....have they changed their procedures?? do you have a phone number for them? I also need some boards and drums...
Edited to add: I just found this thread from last year regarding logicpic....sadly they are no longer in business
http://cakecentral.com/cake-decorating-ftopict-693431.html
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