I need to show this led finger light with a white background. But the light needs to be on and show a little color on that white background. If I just use a brush and white out some area around the light hitting the table then it does not look very good. I want to make a great looking photo to put on the front of this website. I would appreciate any help at all. There is a photo now on the front of this website www.lducompany.com of the finger light but they want me to change it to have a white back ground but show the color light. Thank you.

A couple of things come to mind. You could ask them to send you one of each of the LED's and photograph them separately and then paste them into a new document. Or you can turn them on and spend a little time and a number of photos till you get the right exposure. The last option is probably best.
I attached a pic of their add for the LED's and something I tried.
I used Nik software Viveza to get the brightness etc. on it. Not the best but the best I could do with what I had.

Create a layer set to Saturation and paint white. The blending is by eyeball so might be a little too fake.