I say Ebay and Craigslist. I've flipped over $9,000 starting from zero in just the last 3 months. All summer they've had FREE listings, (you still pay a final value fee).
I go through the SOLD listings, and figure out what sold and for what price, then list mine for a higher starting price. Sometimes you get lucky and get it. If not, the listings roll over a total of 3 times, and you can always lower them. This has also just been selling stuff I'm finding around the house, in my sheds and garage so far... This is all stuff that would have eventually been thrown out, or sold at a garage sale for nothing (nobody pays anything at garage sales around here, everybody else wants it cheap so THEY can flip it!)
Some luck is involved, along with timing, and GOOD PHOTOS and descriptions!