Refurb Macbooks can be hard to come by...
...and some folks just flat out think refurbished Macbooks are some kind of scam - as though the benefits of a certified refurbished Macbook didn't exist. The difficulty in locating these machines stems from Apple themselves. Some time ago they stopped using third party resellers/repair centers to handle refurbished machines and brought the entire operation in house.
This move was great for Apple both in terms of quality control and sales. Everything they refurbish gets handled by their own experts, and sold through their own store. This means they can offer the AppleCare warranty the refurbs, which is also a nice feature.
If was, however, kinda rough on you, the consumer. Competition benefits the consumer through innovation and selection. If Apple's holding all the cards on refurbished Macbooks not only are they difficult to find outside of Apple, the prices they demand are not being adjusted by a competitive market.

So, what can you do to locate these cherished laptops?

1. Take a look at local Apple certified repair centers using Apple's Service Provider Locator. Often these repair centers will have machines they have refurbished and offer as Reseller Refurbs. While not AppleCare eligible, the discounted price can often make them quite enticing when looking for a less-than-new machine. Give your local reseller a call and ask about refurbished machines.

2. Make sure the reseller offers some kind of warranty on their refurbs. This can vary by reseller, but most will offer a 3 to 6 month warranty on the machines. There may be a slight cost associated with the warranty, but any reseller warranty will most likely be considerably cheaper than full blown AppleCare.

3. Poke around on shopping comparison sites, like Google Product Search and Yahoo Shopping. Quite often you can find some great deals on these sites, just make sure you double check the warranties offered on any machines you like.

At the end of the day it's not just about the money you save digging around for alternatives to Apple's refurbished stranglehold. It's as much about making sure you're getting the support you need from the company you eventually go with - and choosing to create sustained competition in the marketplace. Your dollars are votes for the companies and ideals you want to survive, so choose wisely!