It wasn't when I sent the program to Fiance or my sister to proofread. It wasn't when I read over it one last time before giving the Kinkos guy the go-ahead. It wasn't when I sat carefully triming all four sides of each one of the 90 copies. It was when I went to fold the very first one and insert it into its perfect little cover that I found it. A typo.
I'm over it. And I'm not fixing it. I'm just going to cross my fingers that no one notices.