I was getting the maintenance page but it worked in another browser, so I reloaded with Ctrl+F5 to skip cached data and it worked. I then bought 20 dollars worth of coins without a problem. If you've legitimately tried everything suggested then I'm sorry, but people constantly freak out about issues that I've never seemed to be able to not get fixed. Normally I'm not very lucky, maybe it all stores up for stuff like this. Oh wait, that makes no sense.
I don't know why I've responded to all of these complaint threads, but I haven't seen anyone back up Bioware at all, and if you ask me, other than DA2 where they used the same cave for everything, I've never been anything but happy with Bioware and I know there are others who agree. So yeah, there's the other side of it.