Little Black Jumper Blocks?

Where in the world do you get those little black jumper blocks? I can't find them for love nor money! You know, those little black plastic blocks that are on the ends of wires that you plug into a motherboard. Sometimes they are little and have plugs for two jumper wires, sometimes they are bigger and have plugs for four or six or eight or even more jumper wires. I have tried and tried for months, on and off, to find them, but they are nowhere to be found! I've repeatedly visited electronics sites such as MonoPrice, but either they don't have the items or the items are hidden in some obscure little corner the name of which I cannot find.

Is there a special name for them? Is there a place that sells them, not as part of already-assembled units such as USB riser extensions or whatever they are called (the kind that get mounted in an external slot in a computer case), but alone, by themselves?

EDIT: The problem with the local shops is that I want a lot of them to have in stock. It's even okay if they are all, for example, ten-pin size ... I can Dremel them down to size as needed. The local shops rape people for individual parts. Paying $1.50 each or more for plastic parts that should cost $0.02 each in bulk is prohibitively expensive, not to mention personally offensive. There's this place downtown ... they recycle computers and must get thousands of them monthly, which they throw out ... but they will charge me astronomical markups on what they got for free, or rather, for what people *paid* them to take off their hands. Fark that. Scavenging isn't a bad idea, really, but I don't even know where to find a useful place at which to begin, and get the feeling that the shop owners would hate it. I would much, much rather buy a bag of them if possible.

EDIT: I found another thread. These things appear to be called header connectors. In the thread was a link.

http://www.futurlec.com/ConnHead.shtml

This looks like the ticket, only their reputation on ResellerRatings is very bad. Not much point to ordering from them if they will just take the money and run.

I guess I'm going to have to see if the large recycling shop will do barter or something reasonable for a lot of junk they were throwing out, or else really try to find someplace locally where I can scavenge these things whilst no-one is looking.

Yeah go beg some from the loacal shop

That's where I got mine. One problem that you will find, if you locate a mailorder place to get them, is that most places have a minimum order before they will ship.