There are many ways to find books on crochet stitches. You can go to the internet, or the local library, or some yarn shops will also sell them, or even teach you some basic stitches.
The basic stitches used to crochet are: slip stitch chain single crochet half double crochet double crochet treble crochet double treble shell pop corn
The simplest stitches in regular use. You can find a guide to the U.S. stitch names at the Annie's craft store website.
You can count the stitches by looking at either the stitch post or the top loops of the stitch. Don't forget to count the beginning turning chains as a stitch.
You can learn how to crochet from craft books that focus on crochet work. You can find these books from craft fairs, eBay, Amazon, Michael's, Hobby Lobby, and for free at your local library.
Pictures of different kinds of stitches can be found in embroidery books as well as knitting and crocheting books. You may find online tutorials as well that have pictures of these stitches.
There are many ways to learn crocheting online, choose which one (or ones) that work best for you. One way would be to go to youtube.com and search for "learn to crochet" videos, or tutorials. There are many available on that website. Another way would be to do an Internet search for the phrase/s "learn to crochet," "how to crochet" and similar terms. You could also search for specific stitches--such as How to make a: chain stitch, single crochet, half double crochet, double crochet, treble crochet and so on. This should give you another option for finding instructions about learning to crochet. Yet another potential for finding how to crochet online, is to find an online bookseller, where you could search for "learning to crochet" books.
If you are referring to crochet, pronounced crow-shay, where you use a crochet hook and yarn to make things, that is something that has to be learned, and cannot be taught over the internet. You would need to find someone who knows how, and have them show you. There are different types of crochet stitches, and it is not something you can learn without a person to show you.
Search for "granny ripple afghan". There is one at Project Linus and another at Purple Kitty to start.
What one crocheter finds difficult, another person might find easy, so it is hard to say which would be the most difficult stitch to work for you personally. The hardest stitch is probably the first one you learn after the chain stitch, usually either single or double crochet. The stitch itself isn't hard, but it is awkward at first learning something new. Once you know the chain, single and double crochet, half doubles, trebles and all the variations beyond the treble come easily because they are so similar to the single and double crochet. As with knitting, it isn't the actual stitch that brings an opportunity for life-long study of crochet, but the infinite number of ways those stitches can be combined and manipulated. Bobbles and clusters, working around posts, reaching to stitches in rows below, twisting, picots...all of these are simply manipulations of the three basic stitches (chain, single crochet and double crochet). Addition to first answer: A good answer, but -- I once surveyed 12 crochet experts on this exact question, and they all said the bullion stitch.
The coloring books that teach children the alphabet are found at fisherprice website, dltk-teach website, and you can also find them at Dollar General.
One can find embroidery pattern books in most craft stores and good book shops. Alternatively one can try the Sublime Stitches website or blogs like Kinda Wonderful on Typepad.
Go to Crochet.com.