Here are some of the document classes that can be used to create a book using LaTeX:
The default class. Looks dated and ugly.
Looks modern. Better than the default book.
Looks good, but can only be used for math books. This is because all headings are centered (not left-aligned) and all text is center-justified too.
This is from the European designed KOMA package which looks modern and the fonts are nice. While their article class is nice, I did not like the book class that much.
Using this gave me compilation errors which I could not resolve. Thats a pity because this style looks almost like the books from Tufte.
Beautiful book class and my favorite.
Produces beautiful pocket books.
Another nice looking book class.