How do you write a letter of enquiry?

I applied to an academy at college and after an Interview my interviewer told me she would inform me on the success of my application by E-Mail around easter, I have waited a little as its been a confusing time work wise due to all the bank holidays and the royal wedding etc... I wish to keep my letter as polite and formal as possible whilst asking whether I have actually got in or not, I probably haven't as most of my friends who have applied have received a conditional offer and I haven't, still its good to know... :D!