I just picked up a N810. It is my first Linux device so I have no idea what I am doing.
I got it to put Garnet on it so I could run Planetarium for Palm but it doesn't look like Garnet is still available. I never get the email from the access server.
My first question concerns my firmware. My device says it is OS2008 but I see on the Access web page that there is an OS2009. Can I upgrade my device to OS2009 or am I stuck at OS2008?

How many times have you tried to get Garnet? I think it took me a few tries a couple months ago.

OS2008.43-7 is the last version from Nokia, you can and should install the CSSU which is version 2010.33-1 but is still considered to be OS2008 (Diablo). OS2009 is probably Fremantle for the n900.

I tried several times each on both the N810 and on my iPad
I will keep trying every day until the weight of my requests breaks the logjam

I am new to Linux as well as to the N810 so don't know anything about the command line or flashing yet
But today I borrowed Teach Yourself Linux from the library and am starting down that road
Unfortunately all the books I have see are based on a particular flavor of Linux and none of them are Maemo so it is going to take a lot of extrapolating
Last night my machine locked up and I thought I was going to have to blow it away and start over but I don't know how to do that
Fortunately it turned out that the morning email used up all but the last KB of memory so with enough poking around I got enough stuff deleted to get it out of it's infinite reboot loop
But that made me aware of my need to have an image on hand and instructions for using it and now I learn I need to install CSSU, whatever that is
So where do I get these things and find instructions on how to use them
I could also use basic information like how to install programs on my virtually empty SD card which I don't remember reading in the user manual

Maemo is based on Debian, you should be able to find books on it.



http://maemo.qzx.com

CSSU is a community made upgrade to fix some issues with Nokia's last official release. Diablo Turbo is a new kernel with performance improvements.

You can move some files from large packages to the SD card and setup symlinks or you can install Maemo on the SD card and boot from it so your root filesystem has more space and you won't have to move stuff.

CSSU is Community Seamless Software Update, operating system upgrade provided by community, it fixes many bugs not fixed by Nokia and adds some usefull stuff, see http://wiki.maemo.org/Diablo_Community_Project and do as told in "Upgrading to the stable version" section.

You may also want to install diablo-turbo kernel (see this thread for information what it is, there is also a link to page where you can read how to install it).

Maemo is based on Debian, so if you try to find some literature, you may search Debian.

For writing scripts that are run at startup, you may want to read this page. However, keep in mind that if you want to run GUI application (GUI means Graphical User Interface - so it's a normal app with windows, buttons, etc.) it may not be the best place for it (because /etc/init.d scripts may be run before the window system has started, as far as I know, and GUI program needs window system - which in Maemo is called Xorg and Hildon - running).

Good luck!