Unfortunately, 10.1 Community does NOT include any 2.4.x kernels, so you'll have to go to
http://www.kernel.org and download the latest one (2.4.27 is the last STABLE kernel of that series). I just got 2.6.9 for my Slack 10 installation and while it is not difficult to compile and install, it can be rather confusing to configure. Just make sure that anything that currently loads as modules are compiled as modules in your build.
Hope it works out for you.