Mining pool software for home use I have tried to set up a mining pool with my home computers. I am running bitcoind on one machine, and the others, also running bitcoind, were started with --url and --userpass to my central bitcoind server.

Now, are these machines already forming a mining pool? Or am I missing something?

What other software should considered for a home mining pool?
From what I understand, you only need one bitcoind instance on one machine, while other ones would only run miners that would connect to the bitcoind machine. Running more bitcoind than that is not necessary.

As for the software, you should look into P2Pool - it allows you to earn smaller amount of Bitcoins more often, meaning you'll get smaller variance. It won't decrease the amount of Bitcoins you earn on average though, meaning it doesn't cost you anything to use.