CafePress-type online artwork personalizer

[Designermite]

For lack of a better term I am looking for a Online Artwork Personalizer.

Could you point me in the direction how to do a online design form that has the ability to upload your art and personalize with text?

The simplest example I have seen is at:
http://www.ecomugs.com/-c-33.html


other sites that use this:

http://www.cafepress.com/cp/customize/

http://www.buildasign.com


http://www.bluecotton.com/

Thanks