This URL [docs.yahoo.com] gives the street address for Yahoo.
Also, at the very bottom of the Yahoo.com home page there is a link for "Company Information". Since Yahoo is so big, you may need to poke around a bit to get exactly the right contact for whatever your purpose is.
Hello melissa_45614 and welcome to WebmasterWorld.
I don't know the exact answer to your question, but if you look into the forum "Directories: Yahoo, Looksmart, ODP, About.com" you will find more than one discussion about contacting Yahoo. If you set the drop down box "Show discussions" at the bottom of the page to show "All", there will be several choices. If that doesn't do the trick, then post your question again as a new post in that forum, where it might be observed by more people than in this discussion.