For your first question, I find the availability of lecture notes depends on the lecturer.
From my experience at university (note, I studied a STEM subject), I encountered:
1) The entire notes would be uploaded onto the university's online resource (usually known as the "Virtual Learning Environment" or VLE)/lecturer's website etc. so you can print off the lecture notes, read the notes online etc.
The lecturer may elaborate further on the notes and provide extra material so it was not advisable to be absent from lectures and rely on the notes alone.
For this style, I tend to find the online notes may not be released until just before or after the lecture covering the notes.
2) The full printed notes were handed out at the start of the course or sections of the notes were handed out in lessons every so often as you move through the material,
3) No notes provided, so you had to turn up to the lectures to copy down the notes from the lecturer,
4) Notes only covering a summary of the material (so again you had to turn up to the lectures to copy down the notes).
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As for the style I used, I copied down everything the lecturer wrote word-by-word in a exercise book then I would do some background reading afterwards.
As others had stated, it is best to see what is effective for you as my method may not be the best style for you.
Finally, for the situation where notes are absent,
@Mr Wednesday gives some good advice over this.