HowTos usually aim to cover a topic in a fairly practical way, to show how to do something in a step-by-step way. Some of the tutorials here on LQ are HowTos, but some are a bit broader in scope. There is probably no hard and fast line anyway between these categories.
Try the Linux Documentation Project
for a more comprehensive collection of HowTos, and indeed every type of documentation. Or you can google for a particular topic you need to know about.