Before a bid is placed, you can always edit the auction. There should be a button at the top of the auction page that says edit. After the auction has a bid, you can still always add to it, but you will no longer be able to edit the original. Good luck.
:) One more thing... When you reply to a comment, if you will click reply under the comment you are replying to, it will send the original commenter an email letting them know that you have replied. Again, good luck. And if you ever have any questions, I have an unofficial forum where we all gather to try and help one another. If you want the address, just message me...