Image Conversion to Trasparent background

I have 3 jpg images that have white backgrounds (may not be entirely white) and I need them change to have the white backgrounds become transparent and then saved as gif files. I have attached the images, and these images are copyrighted to the owners of the site I am developing. So don't go sending them all over the place please. :) This is my first time so take it easy on me, I am developing the site myself but I am no good at image editing and I have spent 2 hours in photoshop and the result is not good. Thanks Craig ## Deliverables 1) I want the 3 jpg images converted to clean transparent gif images that I can put on top of a blueish background in photoshop to complete my web site header. ## Platform These are images for windows.