Hard_to_Catch2

When you are woking on an Illustration that uuses multiple images either custom created or from stock, do they have to all be converted to PDF and then imported to your canvas on layer, or is it possible to just import them into the graphic as gif or jpgs?

I guess you mean PSD instead of PSD

No, you can open a new PSD file and open all the JPG or GIF files you need and drag them to your open PSD document. Make sure that both images use the the same color mode (image/mode), otherwise it won't work. Every imported image will appear on a new layer.