WD Passport USB only hard drive not respondin

Have a WD "My Passport" 500GB hard drive that has only 1 led, the light is on, but no one is home. It is a simple USB external drive, and it is spinning when plugged in, but not recognized. Have tried multiple computers, multiple USB ports on my laptop. I was listening to music, during that time. I shut down windows player. And since then, my hard drive under my computer is not there. I have been doing research for the past few days. I have seen that it is possible to swap the case with a generic one and see if that works. I am pretty computer savy, and have no problem following instructions. But I have not done anything like this before. Not too worried about replacing, but as everyone else I have read says, worried about the data inside. Many things I would like to salvage if possible? Any direction at this point would be great. As far as chkdsk, or looking at device manager, I have not found anything that might suggest that it is recognized. If I could just be led in the right direction, I would appreciate any assistance on this! Thank in advance for anyones help!

Running Win 7 on my laptop currently and device manager help would also be appreciated! Thank you again!