Serial connection for external product?

hello and thank you for viewing. I have been creating some code for some lights and using others to try and combine multiple functionality within it. At the moment I followed a video to control the RGB spectrum (10 bit of course) with your iPod using a simple app and I would like to do some other things like add sequences through pushes of buttons.

As I hope for this project to be a little cheap I would like to buy one of the atmel chips and put it into a circuit board (well strip-board) and make it run by it self. One problem I looked at is that the chip actually interfaces with serial so I need some help with finding a relevant serial connection to hook up to the arduino. Could any one help me with this? Is there a really simple chip that does this? On my desktop it is a high performance therefore only really having USB and no parallel or Serial connections. So pretty much I am looking for some schematics. I also would like to know if any one sells any pre programmed chips so that I dont have to buy a programmer.

There must be some one out there with the same problem :wink: Thank you all and see you soon!