It's more commonly known as "drop shipping" or "drop ship". There are lots of companies that will do this. You can also approach smaller companies who might also do it if asked. For unbranded drop shipping (i.e. the supplier info is yours), it is called "blind dropshipping".
You could try:
http://www.simplx.com
It may not be where you end up, or you may want a niche, but it will give you a good idea of what kind of programs exist.