When you're a socialite like Nan Kempner, personal stationery isn't just for the occasional thank-you note -- it's one of your primary means of expression. Engraved invitations, personal letterhead, and menus are all done for Mrs. Kempner at Tiffany & Co. (100 note cards with envelopes, $326; wedding-invitation set for 100, $1,017). "They do a fantastic job," notes New York's reigning hostess. "I've dealt with them for years, and they've taken care of all my stationery. It's very quick, and very personal." If even more personal attention is what you're after, you could also turn to Calligraphy Studios (100 Reade Street, 964-6007), which will, by hand, indite invitations with calligraphy (100 invitations, $700 and up), design your personal monogram ($485 and up), or create an entire "stationery wardrobe," which includes personalized letterhead, envelopes, calling cards, and note cards ($2,000 and up), as it has for clients like Natasha Richardson and Quincy Jones.