This pages descibes how to install the OpenEmbedded environment for building Netbook images.
$ cvs -d :pserver:anoncvs@cvs.handhelds.org:/cvs co -ko -roe-vendor oe
The password is 'anoncvs'. If you have a BitKeeper licence, you can use that instead. See http://openembedded.org/oe_wiki/index.php/BitKeeper for instructions in that case.
Now you should be all set. Try “oemake gpe-image” to compile an image. It will probably take a couple of hours and a few gigs of disk. Assuming all goes well, look in tmp/deploy/ for the results.