Ann Johnston is responsible for two books on dyeing - this one and its companion "Color by Design". (There is a 3rd, older book "Dye painting" - but that's out of print). Both books are accessible enough to be good starting points for a beginner - but have enough information to carry on being useful to more experienced dyers. Quite honestly, if you can only buy two books on dyeing, these would be good choices.
Important to note that both books deal only with cold water, fibre-reactive dyes (Procion MX) - that can be used for cotton, linen, rayon and silk. If you need to dye wool or want to know about acid dyes, you need Holly Brackmann's book (or maybe Kate Wells). Also the books are aimed at quilters and other textile artists - if you are an FE or HE student you may need something more technical (try Wells, Brackmann or Kinnersley Taylor).
Color by Accident covers low water immersion dyeing - which produces random, organic visual texture, not flat colour. Look more closely at the cover of the book to get an idea of the effect. The book covers several techniques using one or several dye colours. They're all easy and relatively quick - and you don't need much space or complicated equipment. The book has a good section on basic colour theory for dyeing and advice on mixing different values and more complex colours. An appendix explains the process for high water immersion dyeing - which will produce flat plain colours if that's what you need.
The second book, "Color by Design", is about ways of applying dye directly to fabric using painting or printing techniques. It covers both thin and thickened dyes and looks at the different effects you can get with each. It covers application with brushes, rollers, sprays, fine line tools, sponges, stamps, blocks and rubbings. It covers monoprinting, screen printing (very briefly - paper stencil and photo emulsion)and water-soluble resists. It does not cover discharge techniques. This book also has further good advice on colour theory.
Both books are spiral bound with hard covers and the instructions are extremely clear - recipe book style, which means you can usually go straight to the section you're interested in rather than have to work through the whole book. If Amazon are out of stock, both books can be obtained direct from AnnJohnston.net or Fibrecrafts.co.uk - among others.