Craig's List is probably the best bet, but you'll have to have cash in hand and ready to go as soon as you call or you'll miss out. Some of the thrift stores (Goodwill, Salvation Army, etc.) will have furniture too.
Yard Sales can be found be driving around, Craig's List and in the local newspaper. The WSJournal also has a section in their classifieds for items under $300 which might help.
JournalNow.com
There's also FreeCycle... which is free stuff, have to be quick with replies and pickup. You can also do want ads.
The Freecycle Network
There are also furniture outlets and used furniture stores that might help you find what you're looking for.
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Estate Sale listings for Greensboro, Winston-Salem, High Point
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