Actually you are supposed to send code here. After auction ends, there's an email area up above the auction, that's where you give the code. No through personal email. And Sylvia, you can't remove your credits once they've been bid, if it turns out the code doesn't work, or you do not receive it you can get your credits back, but it takes a few days unfortunately. Above the auction where email can be sent between you and the lister, there will be a question asking if everything went okay or do you want your credits back, but I don't think that shows up for 3 days or so. If you really don't want this your only hope is that someone outbids you. Good luck!!
Grizzlies, you need to get verified through Listia. Go to your home page and scroll down look to the left you'll see an option for getting verified. Until you do that, people are going to be wary of you and therefore you won't get bids. FYI. Good luck
One more piece of advice, get verified now, it only takes like 2 minutes and the bidding doesn't really kick in until the last hour til end of auction. You have lots of time and it'll be worth it to you!
Email here, or personal email? Tybo's half right. You can send the code through email here, but if you so wish to you can send it through personal email.