jQuery Simple Transition is a light weight plugin which enables you to have different kinds of transitions between images. See the expamples below.
This is the little snippet of code which is used to make the transitions on this webpage. This might be useful for you.
The below is my HTML
This is my JavaScript
If you have linked the jQuery library and the jquery.transitions.js to your HTML properly and you have added the two snippets of code properly then you will end up with a nice transition effect.
* Note: please remember to link the CSS files before the javascripts.