Snowleg by Nicholas Shakespeare
When a young Englishman visits Cold War Leipzig with a group of students, he meets an East German girl who is only just beginning to wake up to the way her society is governed. He wants to help, but her situation makes him nervour. He ends up in denial about his feelings for the girl until one day, with Germany now united, he sets out to find her. But he has no idea where to start - all he knows of her identity is the nickname he gave to her - Snowleg.