aaaaaaaaaah, ok well that first link has 2 links in near the bottom with pretty decent guides to get you started, wont be "turn key" scripts though, you will have to come up with some of your own
You wont need a complicated distro, almost anything will do, I like slackware myself.You will need all the networking tools.You will also need to learn how to use iptables and a few other things.I didnt read thru all of it but youve got me curious now, Id like to know how they throttle the packet flow, I know it can be done, but never seen how myself.