In the late eighties I bought a book by Al Stevens which provides some of the information you would need to write your own version of Sidekick.
Specifically it dealt with writing programs which could generate on-screen windows (stacked, layered, etc,) and also how to create TSR programs.
I liked the book so much that I still have it after all these years. I learned a lot about writing C code from this book.
I searched on the web and I couldn't find an image for it so I scanned the front and back covers of my own copy and you can see them below.
I did see on the web that you can but the book from Amazon. The price which is printed on the back of the book is $24.99. One of the listings gave the condition as " Used - Very Good. Very nice Copy - almost no wear". The price quoted was $369.98 plus shipping!
So if anybody would like to send me $400 or so then I would be happy to give you my copy, which is also in very good condition!
