Due to the weight of the boards, it's very difficult to find a website that will send them to you at a discount that won't be off set by the shipping cost.
Personally, a couple of years ago when my LCS was getting ready to order another bulk of them from their suppliers, I spoke to the manager and he ordered an extra thousand B&Bs just for me and gave me a little extra discount off it. I saved a couple bucks off the normal discount I got on supplies when I buy 100 at a time, he made a bulk sale, and I didn't drain his supply since he was making the order anyway.
I think I've done that two or three times now, each about a year apart. At the time, I had a lot of unprotected comics waiting to be bagged, and then I was left with extras to handle the new comics I bought for the next several months, so I wouldn't accumulate too many more unbagged issues.
I dunno if this'll work for you, it depends on how many comics you have waiting to bag, and how many you buy a month going into the future, and if your LCS guy is willing to have a similar arrangement with you. Given that 100 B&Bs are about $15, give or take and depending on what discount you have, a thousand would be $150, minus whatever extra might get shaved off for the bulk order. So it's somewhere under a $150 investment, and I dunno if you're tight on cash or anything. Generally, if you want the best discount on anything, you'll get a good one by buying in bulk. If you like your comics bagged and boarded, you'll want to get these eventually anyway, and you can save a few bucks by getting a lot of them sooner. But, like I said, depends how many you have waiting, and how much you buy regularly.
