Good observation about the beak and what kind of tree it was in - now, approximately how big is the bird? For instance, smaller than a pigeon, the same size or bigger?
Color of the rest of the feathers - as close as you can tell
Which state are you in and what area of the state (city/town/county)?
It sounds like you're a birdwatcher, or at least a backyarder. They are fascinating aren't they? I've found some of the most unassuming looking, little birds can have the biggest, most beautiful song.
Let's try to figure this one out. I'll provide some links here with photos and you can try to match up what you've seen:
This one seems a bit small from your description, but perhaps it was a Red Breasted Nuthatch http://www.hww.ca/hww2.asp?id=66
Another small bird and more red than on the breast, a Scarlet Tanager
Common Redpole http://outdoors.webshots.com/photo/2216199690098966149qFzziQ
Orchard Oriole http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Orchard_Oriole.html
A Baltimore Oriole doesn't just swing a bat, the original has feathers and the breast can be an 'orangy-yellow' http://animals.nationalgeographic.com/animals/birds/baltimore-oriole.html They are one of your native birds.
The Eastern Towhee http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Eastern_Towhee.html
Finally, but by no means the end of the possibilities, the American Robin can be pretty large http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/American_Robin.html and are nest builders as you describe.
The Nature Conservatory in Ohio has a list of other native species you can consider and be on the look out for. A sort of guideline to backyard birding.
By putting out the appropriate foods at the right locations you can have different flocks of visitors throughout the day and year 'round. Keep it up!
That's always the way isn't it? The simplest answer is often the right one.
Well, now you have a list of other native species to be on the look out for .
Do not press 'accept' again. I'm happy to follow up as often as you need on this.