Basically, I am writing a book which I plan to self-publish via Amazon for commercial purposes. What I am mostly concerned about, is whether I can legally quote from websites which are protected by copyright. The quotes would be very insubstantial, a couple of sentences long max, and probably less. Would that qualify as "fair use"? What about quoting not from websites but from other books? Would it be fine to quote from a book published within the last 10 years without seeking the permission of the author granted that the quotation was short and not of particular significance?
You should be well within the fair dealing rules for quotation in all of the cases you have described. But you must make sure that you mention the source of the quoted pieces. For a website just the URL may suffice if you don't know the name of the author, and with a book, the author and title should be cited. You can find additional guidance on the quotation exception and what fair dealing means in this IPO Guidance Note.
3.1. The Website contains copyright material, trade names and marks and other proprietary information, including, but not limited to, text, software, photos and graphics, and may in future include video, graphics, music and sound ('Content'). The Content is protected by copyright law, registered and unregistered trade marks, database rights and other intellectual property rights.
I can see why you are confused. There are two separate things going on here. The first is the conditions of use stated by the site owners. Think of them as similar to the conditions of entry into a music venue - no flash photography and no alcohol to be taken in, for instance - which form the basis of a contract between you and the web site. If you fail to abide by these rules then the site could, in theory, ban your IP address from using the site again, or some other sanction.
They justify these particular rules on the need to protect copyright and other intellectual property rights, but this is where the law of copyright overrules such terms and conditions. If I had provided a link to the relevant law in my previous reply you would have been able to see this for yourself, in section 30 of the Copyright Designs and Patents Act 1988, subsections (1ZA) and (4). This last subsection says:
(4)To the extent that a term of a contract purports to prevent or restrict the doing of any act which, by virtue of subsection (1ZA) [the quotation exception] would not infringe copyright, that term is unenforceable.
I have cleared about 700 permissions for the books I published and I can tell you that some writer's agents are very picky indeed about granting permission.
Sorry to have to disagree with you on yet a further issue. The quotation exception is fairly new - it was only introduced in the Autumn of 2014 - and covers any sort of quotation. I think you may have in mind the older fair dealing exception for the purpose of criticism or review which did require a certain amount of relevance between the work being quoted and the subject matter of the work containing the quote.
The quote is :
“It is very, very easy not to be offended by a book. You just have to shut it.”
(I have no idea where it was originally said or published.)
Somewhat amusingly, you have answered your own question by actually quoting the passage you want use! There's no practical difference between quoting something here on a forum and quoting it in book. The answer is yes, that quotation would most certainly qualify for the fair dealing exception as long as you attribute it to the person you believe authored it.
Am I able to use song titles as chapter headings? The titles used would only have a loose connection to the story content.
2. MATERIAL GIRL
...where, in chapter 2, the female main character works in a dress shop.
3. HARD DAYS NIGHT
... where, in chapter 3, the main character works a night shift. And so on.
I wouldn't necessarily want to include the artist name - though that could happen. Is any of this allowable, do I need attribution?
Titles of books or songs are usually treated as not being subject to copyright because they are either too short* (say, fewer than 6 words) or unoriginal, or both. So on that basis I don't think there is any risk in using song titles in this way, and because this is not fair dealing you don't need to worry about attribution.
* de minimis in the legal jargon.