I recently bought some parts from Holley through their Ebay store:
http://stores.ebay.com/Holley-Performance
Brand new parts - EFI stuff that they don't use in their latest kits - in their original packaging and I paid less than half the retail cost. They were exactly what I needed and a killer price.
I'm not here to promote Holley, simply to say that I wish I knew about their "factory outlet" Ebay store earlier as I've bought other manifolds and carbs in the past.
Are there any other large auto parts companies that sell factory refurbished or surplus stock at great prices (either Ebay or through other channels) that you've found? I'm always keen to save a few bucks!