Javascript wanted to allow web users to design their own badges online

I am looking to purchase an existing business that sells badges.

With this site I want to allow users to design their own badges by uploading a photograph, crop it, add a bit of text etc.

I am not after photoshop on the web - but a basic image editor that would allow users to design a badge within a certain template structure.

I have found a couple of sites that offer something similar, but their code is beyond me, but it doesn't look like rocket science.

For example, look at this page: http://www.badgeplanet.co.uk/designyourown.asp?mode=new

This uses javascript and layers to create the illusion of designing online (if you add a clip art image for example then move the layer to the left continuously you will see that the clip art image appears again from underneath the badge template)

I want something like this - but smarter looking :-) and flexible enough to allow me to apply different badge templates (ok, on the example site it's a transparent white graphic)

Once the user has designed their badge, I then need to be able to have the graphic file saved to my website and their shopping basket, which I am assuming is just a case of the image being saved and the filename being passed along with the form.

I would want the whole javascript to be in one file that I would then "include" at the appropriate point on my webpage ... because of how I envisage developing the site once I've purchased it I will want the editor to appear on different pages throughout the site.

Hope this makes sense - if not, ask me any questions :-)