In an effort to free up space on my disk drive I accidentally deleted my audio device. I think it was called a Realtek...

There are many realtek sound devices could you gives us some information
on the make and model of your PC.

Alternatively you could do a hardware scan here Hardware Scan | D-A-L Computer Help
and post a link to the results found at top of the results page here.

Jim

This may help as well;

Download, install, and run Everest Home Edition on this machine. (CLEAN FreeWare) Once it's finished loading and
running, click the + sign next to;

Motherboard. Click on Chipset. Post the information listed under South Bridge exactly as it is listed.

Multimedia. Post the information listed under PCI / PnP Audio exactly as it is listed.

How did you delete it? Did you delete the files from your hard drive? A System Restore to before you did this may fix the problem.