The challenging part here is to start with the right type of photocopy. Make sure you get advice on which printer to use for transfers and what settings.
In our area Staples self serve color machine set to black and white (check it is the right machine as the newer machines don't work for transfers). Kettle valley graphics in Birch Plaza are helpful and very very knowledgeable.
If you want to purchase a printer for transfers, it's not an ordinary ink jet. The best printer is the type of laser printer with powder drum toner, but get advice as they are not cheap.
For color use Golden soft gel. Coat image with soft gel, place face down on object, smooth or rub with back of spoon to remove air bubbles. Allow to dry. Wet copy with sponge and gently rub off as much paper as you can with your fingers without removing the transferred image. When dry, apply two coats of wax, drying in between.
Copyright free vintage photos can be obtained from graphicfairy.com
Nancy Crawford in Langley BC has books on the subject.