I work with Canvas Press and we specialize in creating custom canvas prints. If you want to make your own canvas prints there are a few ways this can be done. The best option would be to print the canvas yourself and then stretch it. You will need a quality printer, canvas material to print on (I believe HP or Epson make some). You will also need wood stretcher bars, a mitre saw to cut the stretcher bars at 45 degree angles, a nail gun, and a stretching clamp tool. Once you have built your stretcher frame with the mitre saw and joined it together then lay out your printed canvas face down and place the stretcher frame on top of the canvas. Wrap and staple one end of the canvas (make sure it is straight. Then turn the canvas and use the stretching tool to get a nice tight fit, stapling as you go. This process can take some time and practice.
I think you should you use a good website to print your photos on canvas like Magnipic - http://www.magnipic.com/stretched-canvas - it will provide you good quality prints.The most important accessory in canvas printing is a stretcher. It is a wooden frame which helps to stretch the canvas and provides a smooth and flat surface.