iahphx:

the situation is really strange regarding the credit cards !
if ctrip and elong messes around with you, go on www.yoee.com, they have basically the same prices and I have successfully used foreign credit cards on that site as well, never a problem. (apart from the fact that sometimes the cc input pages only show up in chinese and you will have to guess haha)
when it comes to preferences, I usually go with China Southern or Hainan.