First one is ActionOutline. It comes in 3 versions – Free (lite), Standard ($39.95), and Pro ($79.95). Pro can be used to share docs in a network while Standard is stand alone.
Instead of the file/folder format of MS OneNote, ActionOutline (and TheGuide as well) use the tree format – which is also useful.
Second is TheGuide. This one is free.. and has basically the same functionality as the Standard version of ActionOutline has. So, I would go with this one. Rather interestingly, it also provides support for a number of languages – like Malayalam, Hindi, Tamil, Greek, Arabic, Sanskrit, Russian, Chinese, Japanese, Kannada. So you can choose in what language you want to write your notes.
Important feature – you can search the entire tree or a subtree – this feature in OneNote has been a big blessing for me at times!
How can it be used? You can give a structure to any “project” – IT project, Home assignment a novel, research paper, Book list, list of recipes, travel itinerary or business proposal – and then fill in the information you want.
I haven’t tried these two myself so I cannot talk about their performance, but from the look of it and because it is free, I will definitely try TheGuide!