If you want to send a letter protesting the funding cut to the Poe House, here's the address to use.
Office of the Mayor, City of Baltimore
100 North Holliday Street
Baltimore, MD 21202
I beg my readers to please, please, please be polite, to express an understanding that times are hard, but also express your feeling that a landmark like the Poe House needs to be preserved as part of the cultural heritage of the city of Baltimore, if not the country as a whole. Tell them that without the Poe House, there's less reason for you to visit Baltimore and spend your money there.
No threats, just be measured, polite, yet disappointed and maybe a bit angry.
By the way, the Mayor's name is Stephanie Rawlings-Blake, so please don't embarrass yourself with "Mr. Mayor." If you're going to name her on the envelope, please refer to her as "The Honorable Stephanie Rawlings-Blake." Open your letter with "Dear Mayor Rawlings-Blake," and in the body you have three options; "Mayor Rawlings-Blake," "Madam Mayor," or "Your Honor." A dignified, respectful tone will serve you much better than incoherent outrage. After all, my readers are people of class and distinction, so don't let me down.