Some time ago I uploaded a map of a noble mansion I had drawn by hand. (can be found here) The question of where I got my inspiration came up, but unfortunately all my resources were German. Still I found the tutorial I used very helpful. Thinking it was a pity I couldn't share it with you I addressed the author and he gave me permission to translate it.
So here it is, a short summary of a workshop about Drawing Plans. For those who are not interested in the whole story but just the tricks and methods I added a handout at the end that basicly sums up the main points.
I hope it's as useful to you as it was to me