This site allows you to generate proxy cards for the Magic: The Gathering trading card came. The images are hosted here, and are adapted from the ones uploaded by the team over on the Slightly Magic forums.
To create a deck, enter the cards in the large text area below, one card per line. If you're unsure of the card name, the box on the right will attempt to autosuggest card names if you start typing! (requires Javascript)
If you still cannot find it, there is a list of every card (up to Worldwake) here, or use Gatherer.
Comments/suggestions and any other correspondance to edd {at} edd-miles {dot} com
If you're using Firefox, Chrome or Safari (Internet Explorer and Opera coming as soon as I can work out how to hack the javascript together) you can select which image you want. When you have your card pictures, just click on the image you wish to change. The image should cycle through all printings of that card. My list of cards is missing some of the promos, but otherwise is complete.
All images are © Wizards of the Coast and/or their respective artists.