Check your junk folder for the mail. Perhaps it went into there. I'd contact yahoo after 10 days about this. If they don't list you, get money back. When i have the extra cash i may submit to the directory. Or just wait it out and see if DMOZ add's my site. Prolly take a year for them to do this. lol
It says 7 business days which work out to 9-11 days barring a holiday. I paid on 04/25 and received an email saying I was in on 05/03 and my site would appear in 2-4 more additional days.