There are two main kinds of Intellectual property (IP) that might be relevant in writing such a guide: Trademark and Copyright.
A Trademark protects against the use of an identifying word, phrase, design, logo or symbol in the course of advertising or trade by someone who is not the trademark holder without permission from the holder. Specifically, one may not use a trademark to make it appear that goods or services are produced, authorized, or endorsed by the trademark holder. One may not use or imitate a trademark in such a way as to confuse consumers or potential consumers about the source of a product or service. If, for example, you use an apple logo on a computer product. and you are not Apple Inc, nor have permission from them, you may well have committed infringement. Infringers may be sued, and significant damages recovered.
There are, however, some key limits to trademark protection.
Nominative use, also known as "nominative fair use" in the US, is the use of a trademark to identify the product or service being referred to. It is not an infringement to use a trademark to refer to another's goods or services, provided that consumer confusion does not occur.
Specifically, 15 U.S.C. 1125 (Section 43 of the Lanham Act) (Paragraph (c)(3)) provides that the following are not* infringements:
(A) Any fair use, including a nominative or descriptive fair use, or facilitation of such fair use, of a famous mark by another person other than as a designation of source for the person's own goods or services, including …
(i) advertising or promotion that permits consumers to compare goods or services; or (ii) identifying and parodying, criticizing, or commenting upon the famous mark owner or the goods or services of the famous mark owner. (B) All forms of news reporting and news commentary. (C) Any noncommercial use of a mark.
In the US court case New Kids on the Block v. News Am. Pub., Inc., 971 F.2d 302 (9th Cir. 1992) the 9th Circuit Court of Appeals held that
a commercial user is entitled to a nominative fair use defense provided he meets the following three requirements: First, the product or service in question must be one not readily identifiable without use of the trademark; second, only so much of the mark or marks may be used as is reasonably necessary to identify the product or service; [FN7] and third, the user must do nothing that would, in conjunction with the mark, suggest sponsorship or endorsement by the trademark holder.
The footnote (#7) says:
Thus, a soft drink competitor would be entitled to compare its product to Coca-Cola or Coke, but would not be entitled to use Coca-Cola's distinctive lettering.
Thus the general rule that Logos don't constitute nominative use. This limitation on nominative use may be different outside the US.
A specific form of nominative use is using the trademarked name of a product to show that the product being advertised or sold is compatible with the referenced product.
WonderBatteries can be used with BrandX tools.
Such a statement may be made without permission of the trademark holder on "BrandX".
A claim such as:
BrandA provides a better user interface than BrandX.
May be made while marketing BrandA and is not an infringement of the trademark on "BrandX", provided that it is made clear that BrandA is not supported or endorsed by BrandX.
Use Not in Trade
A publication, such as a user's guide, or a third-party (independent) review, which is not selling or advertising a product, may use trademarks to refer to the products that they represent without infringing those marks, because trademarks only protect against the use of the marks "in trade". This is rather like nominative use, but is broader. If the person using the mark is not selling or advertising anything, there is no protection at all, and graphic marks may be used as well as mere names. So a Book "All about Windows 10" could only be advertised with the name "Windows 10", but the book itself could make use of the windows or Microsoft logos, provided that the book is not itself advertising any product or service.
US First Amendment limitations on Protection
In Matal v. Tam, The IS Supreme Court ruled that trademark protection, as a restriction on speech and writing, is limited by the US First Amendment. This means that many traditional "dilution" and "tarnishment" actions will no longer stand up under US law. See sources cited in What is trademark tarnishment or dilution under US law?. Such limits apply only under US law.
The author of a guidebook must also be concerned with copyright protection. Short phrases, such as titles of books, and the names and slogans of products, are not protected by copyright at all.
Passages of significant length, however, are generally subject to copyright protection. Facts and ideas are not protected, but the language used to express facts and ideas often is protected. Unless permission has been secured, an author may not copy extensively from a source, nor closely paraphrase the source. The author must rewrite in original language, although the ideas my be taken from a source or sources.
Fair Use or Fair Dealing
Limited quotations, which should normally be clearly marked as quotations, and clearly attributed to their authors, may be used without permission under the concepts of Fair Use (in the US) or Fair dealing (in several Commonwealth and European countries). The exact scope of these exceptions to copyright protection is different in different countries, and is highly fact-based, so that there is no clear formula which will mark out legitimate fair use from infringement. Short quotes, clearly attributed, which would not substitute for the source nor harm the market for the source are likely to be considered as fair use or fair dealing.