Programming in BASIC
A beginner level tutorial that's easy to understand. It teaches
(Q)Basic from the ground up, without assuming you've ever
programmed before. Everything is explained in great detail and as clearly as possible
QBasic - Step By Step
QBasic tutorial covering fundamental aspects of the language, input and output, control structures, modules / sub procedures, looping, functions, arrays, array-type problems, records, and data files.