Note to Amber:
I received your email about finding "t shirts that are totally plain with a scoop neck and it has a little extra material around the scoop neck" and I think I can help. I am not sure how embellished you want the neckline, so I found a few options for you, hopefully one of them will solve your scoop-neck shirt conundrum. The shirt in the above photo is from Downeast Basics and can be found here. I also found another more colorful option from the same company, here.
If those are not what you are looking for, there is a DKNY shirt that you might like here. If you want more of a plain t-shirt you may like this James Perse option or possibly this Marc by Marc Jacobs shirt.
If none of those are what you are looking for, J. Crew usually has good shirt basics, as does American Apparel and I love the Hanes undershirts found at Target.
Hopefully that helped Amber, and thanks for reading.
Note to Readers:
If you have a question about your clothing, style, wardrobe, etc. don't be shy! Email me (firstname.lastname@example.org) and I'd love to help. It's the least I can do for you reading Fashion Noted.