Linux uses a system called SANE (scanner access now easy) to support scanners, and should auto detect your scanner so you can use it without installing a driver.
read this to understand what SANE does.
Now -if- your scanner is supported, which with HP is often the case, although with all-in-one's its a lot more problematic, you do not have to do anything to use it.
Here you can find a list of currently supported scanners under SANE.
To see if your scanner is supported simply try to scan! Turn on your scanner and then turn on your PC, (so that gOS can "find" the printer/scanner during boot up time) Now open the program "The Gimp image editor". In the main screen of the gimp open the "File" menu, and then the "Acquire" menu, now -if- gOS has a SANE driver that is suitable for your scanner, you should see it listed as an "Acquire" option (otherwise you would only see the options "Post as New" and "Screenshot...", (which is one way to make a screenshot by the way). If not this Linux distro does NOT have a suitable SANE driver installed for your scanner. Sorry :-(
But hold on! I know you are using gOS 1.0.1, because you say your printer is working, but lets say you were using gOS 2.0.0-beta1 (the version WITHOUT the large analog clock), then note that you are using a DEMO version of gOS which only supports a LIMITED number of devices!
In that case it would be better to scrap it, and use the "normal" version gOS 1.0.1.
But note that there is also a -new- gOS in the pipeline, one which is hopefully coming soon, and which you could try later. It's called gOS v2 (also called "rocket"), this is the definitive version 2, and is completely different from version 1 and the beta version 2. You could try to use it, (when it comes available) if gOS 1 does not support your scanner, as maybe if its a recent scanner a driver has come available for it.
addendum from LinuxChick As well as sane, to scan with an HP all in one, you need to use the HPLIP driver. Check in Synaptic to see if you've got it or not.
source: mahjongg at []