Here’s where I buy stuff. Opinions are my own; I’m not getting paid to say any of this…
A General Observation: most surplus outlets have a mix of “real” surplus parts and quasi-retail stuff. The former can be pretty good, but the retail stuff tends to be bottom-dollar Chinese crap that’s not worth the money.
Electronics Goldmine www.goldmine-elec.com
Serious electronics surplus with a nice selection of SMD parts. You can stock a pretty good workbench from their surplus parts; some of the tools are OK.
American Science and Surplus www.sciplus.com
Their true surplus stuff is pretty good, but pay attention to the General Observation. Corroded button cells, a “gasoline siphon” that dissolved in gasoline, wire strippers that broke on the first wire.
Before you buy anything retail, spend a while tracking the RSS feeds from techbargains.com and xpbargains.com. I tend to buy cheap-after-rebate end-of-life stuff that’s perfectly serviceable and costs maybe 10% of the original price. Why buy from eBay when you can get it retail for less, with free shipping thrown in?
All manner of batteries, decent prices. The last batch (late 2008) of their house-brand AA cells had half a dozen dead-on-arrival cells and several early failures.
Replacement batteries, individual cells, packs, and chargers. Regular coupons & free shipping.
I buy a lot of Dell PCs, mostly because they tend to work and prices seem to be no worse than anywhere else. Pay close attention to techbargains.com and get ‘em when they’re cheap!
Mostly, I use Free Software and tend to not buy closed-source stuff.
We’re running various flavors of Kubuntu, with the x86_64 version on my Dell Dimension 9150 desktop. That choice turned out to be suboptimal; Flash is very fragile and there’s no official Google Gears release. The next time I update things, it’ll be back to 32-bit land for me…
Stuff I do buy:
Printer drivers with all the bells & whistles for my printers. Basically, the Free Software reverse-engineered drivers simply didn’t work.
Schematic capture & PCB layout. They have a free version for small boards that’ll probably do what you want; I paid for the low-end version to encourage them to keep it up.