APX100 bulk rolls on Ebay
$22.95 per - he had 20, but I just splurged and bought five. I've never used it before, but I figure if the raves turn out to be true I want to have enough to last a while at least.
The seller also has rolls of APX400 for $24.95.
These have been on thier website as well:
APX100 bulk rolls, $22.95:
APX400 Bulk rolls,
I don't know if they are getting down to the last 20 rolls, or if that number is only an eBay thing.