Well I finally did it and I must thank Bill Carr for giving me the specifics so I would know exactly what to do. So I visited this page and emailed the facility at College Park, Maryland.
http://www.archives.gov/global_pages/conta...tact_us.html#em
If you are looking for info on a specific unit, then you scroll down the page until you see the section:
I have a question about research and records at NARA
Then you simply fill in your request being specific as you can. When you are finished, then you fill in the Contact Info located at the bottom of the page. That's it.
They say it usually takes several weeks, depending on the information that you are seeking. Please note that this is not a FREE service. Bill wound up spending approximately $260.00 to get his father's unit records.
NARA will contact you and let you know what they have found and how much it will cost.
I will keep you posted on the results. I am very excited about this leg of my journey. This was something I had wanted to do for months. Wish me luck! 
Proud Daughter of Walter (Monday) Poniedzialek
540th Engineer Combat Regiment, 2833rd Bn, H&S Co, 4th Platoon
There's "No Bridge Too Far"