Hello.

Please see http://talk.maemo.org/showpost.php?p...&postcount=112 - read the rest of that thread to gain more knowledge, but basically you need to download 2 files attached to that post, remove ".txt" extention form them and open them on N900 - it will add unofficial backups of Nokia repos that were shut down. It's hard to install something on "fresh" N900 these days without them. There are many threads about that, but maybe you searched without proper keywords

Next, see https://wiki.maemo.org/N900_The_Perfect_Setup , especially parts about CSSU, power kernel and swap on sd.

If you get this message in terminal ("are you root?") it states you need to be root to perform some operations. Please open Hildon Application Manager (the gui app manager from N900's menu) and install the package that is called "rootsh" as far as I remember - then you will be able to type "sudo gainroot" in terminal to increase your permission level and perform some operations.

Good luck and have fun, but I feel like you're not experienced with linux, so please know you might break stuff (I suggest you install backupmenu and make a full backup once you got cssu and kernel power installed and everything configured).