Outside of QuickBooks _ Depending on what needs to be included, it might make more sense to print the disclaimer on the back of the form. It would also be possible to use this method in conjunction with option 1 or 2 to state something along the lines of "see additional disclaimer information on the back of this form" to include a reference to the information without having to actually include it on the form.
This is nothing different from a document file, but you can work on it to publish on web directly as a web form template. This one is the latest feature of word. You have several integrated programs to improvise your templates in terms of visual appearance. You also have the option to work with the add_ons in MS word. If you work wisely, you can bring out a professional template all by yourself.