Hi! I just installed Linux, and am currently trying to install ALSA to get my sound working. But everytime I try running the configure, I get the follow at my last few lines:

checking for directory with kernel source... /lib/modules/2.4.20-18.9/build
checking for kernel version... The file /lib/modules/2.4.20-18.9/build/include/linux/version.h does not exist.
Please, install the package with full kernel sources for your distribution
or use --with-kernel=dir option to specify another directory with kernel
sources (default is /usr/src/linux).

It seems that it is able to find where the kernal is, but I don't understand what it means by me having to "install the package with full kernal sources for your distribution". I even tried installing the Kernal Development package, and it still doesn't work. Can someone help?

Thanks

You need to have a copy of your kernel source code in /usr/src/ so that the alsa compilation stage can pull some includes out of it.
In your case you need the kernel source 2.4.20-18.9,
am I right in guessing this is the kernel that came stock with your distro? (eg, redhat, mandrake, gentoo, etc...) if so, you should be able to install the kernel source as a package from one of the cds.

The kernal that came with my linux cd is 2.4.20-8, and then I updated it to 2.4.20-18.9. Included in the Kernal Development package would be the source to 2.4.20-8, so should I upgrade the source to 2.4.20-18.9 as well?

right, you need a copy of the kernel source code for the kernel you are using. Older kernel sources won't work.