Right click on the project file, click add new, general tab, text file. Name it in the box. It then appears in a folder called "Other files".
You could also try linking the QFile to the file location: C:\Items.txt.
"QFile items("C:\Items.txt" "close bracket" ; //keeps making a smiley with this last bracket
//then you can go:
items.open(QIODevice::Readonly); //as if you had the file in the project itself but, the above of adding the text file to the project should work.
I would suggest using Dev C++ for this module, Qt is part of the visual programming module later. Qt also has it's own library and many of the other functions you usually use will have to change assuming you are using Walter Savitch's book. That is unless it is recommended that you use Qt for this module.