Usborne has released PDF scans of their old programming series for systems like the ZX Spectrum and C64. These are some of the first programming books I ever read, specifically the Machine Code for Beginners and "Introduction to Computer Programming", both of which I discovered at the library at age 8.

I actually had at that point access to a C64, and spent the time typing in the sample programs.

All books are here, on the right-hand-side of the page:

http://www.usborne.com/catalogue/feature-page/computer-and-coding-books.aspx

Only thing I still remember from these books are the illustrations.