I read the post that said to delete all files and abandon an account to cancel it.  However I singed up for a trial account to test for a client.  We now want to sign up for paid service, but we used several of our emails addresses for testing.  Now when I go to add those users it says the email is already in use.  How can I fix this?  Have already deleted all files from test account, and those users were deleted from that account as well.

In this case, please email us the usernames / email addresses, we can help delete them;

If these users are your sub-users, then you can use the "Group Admin" link to delete or edit them.