If you want to put photos and images on chocolates, consider edible inks and frosting sheets. I spoke to a representative from Kopykake, a leading company selling the products, and it was explained to me how their system can be used to make custom chocolates.
Basically, you would take a frosting sheet (icing sheet) and put an image on it using edible inks. The sheet is layed into a chocolate mold and a layer of chocolate is added. (According to Kopykake, it is best to use white chocolate as the colors may be affected if milk or dark chocolate is used) The sheet will asborb into the chocolate, leaving a seamless image.
There are many different ways to get an image on the frosting sheet. You can simply draw on it using edible ink markers, you can trace a picture or logo and color it by hand, you can airbrush it, use a rubber stamp dipped in edible inks, or best of all use a printer or scanner. Using a printer or a scanner, an image is transferred to the frosting sheet in brilliant color just like printing on a piece of paper. You can do photos or whatever type of computerized image you want.
The Kopykake system is great because the frosting sheets are already made in pre-formatted shapes such as circles, squares, hearts, and business cards. They also have free software that allows makes it easy to add text and graphics. They also sell edible ink cartridges that fit into many Epson and Canon inkjet printers that can be bought off the shelf at any store.
One really neat project is to make an edible photo in a chocolate picture frame. To do this, you would get a picture frame mold and a print a photo onto a frosting sheet. Put the printed frosting sheet in the mold frame where the picture would naturally go, add the chocolate, and you're left with an edible picture in a photo frame.
If you don't want to get into making the frosting sheets yourself, there are companies on the internet that will make them for you. It is much less expensive than having a custom tranfer sheet made. A transfer sheet is different in that it is an image actually printed in cocoa butter. Only the cocoa butter image is transferred onto the chocolate if you use a transfer sheet. A frosting sheet is a bit different, but it still provides the roughly the same result.