If there is a tree lot, around often they will give you the trimmings for free. I know lowe's & h/d will do this. I grab the boughs for decorations, but often as not don't end up using them for that and instead use them for mulch for my acid lovers. I also cut off the branches of the tree when we take it down for the same thing.

There should be a wholesale florist in either Greenville or in Spartanburg - try there. Ask your local florist, if you can't find any other source - but I know it is possible to buy large boxes of clippings of boxwood for decoration, so would imagine that boxes of fir branches should be available....

As Tamelask says, try the nearby X-mas tree places - they do trim up the trees to suit the customer, and have to do something with the off-cuts - there might be a small charge for them, depending on the source...

You will need a retail license to buy from the local wholesale florists.
I would try HD and Lowes as tamelask suggested.
I noticed Lowes has douglas fir wreaths at 9.99.
I am a retail florist and my wholesaler's price is higher than that.

Thank you all for your responses. I had no idea I could get stray boughs from Lowes or HD. I only need enough for one or two wreaths so that should work out great.