Can you explain what you mean by "(but that may have been messed up by posting here without using the code buttons)". Not sure what "here" refers to or what "code buttons" mean.
You need to put code posted in the forums inside backticks (use the code button just above the post form) -
http://codex.wordpress.org/Forum_Welcome#Posting_Code
Doesn't sound like that's the problem - don't know where they'd be coming from - so yeah, negative margin may well work okay - try:
#post--9999 form input {
margin-top: -20px;
}