Can't add them to your cart anymore from the website, and you can't buy them online for in-store pickup either. I went to my local CC, they had none. Tried the local Best Buy, and someone had beaten me there -- when I asked if they had any, they said some guy had just bought all of them. Went to Wal-mart, and they had a ton, but they wouldn't price match because of the way the deal was set up.
I went back to CC and tried to order them, and eventually found some in stock at another store not too far away and bought them there. It took about 15 minutes of "discussion" with the manager for him to sell me them at $9.99 each...at first he said I had to buy the console, then that they weren't an accessory, but eventually he gave in and sold them to me.
Another possibility is to try to get them to apply the discount to the $25 Zune cards. They are good on XBox Live, but only come in $25, so it's not as good of a deal if they'll honor it on them. However, it's better than not getting any, and the store had about 100 of the $25 cards (2000 points). I asked the manager if he would price match them, and he said no, but I'm sure the more experienced Hot Deals members could probably convince the manager to do it.