Specifically, if I am looking for a very specific type of book, if one even exists, is that prohibited and if yes, why?
I ask because I would much rather ask the community for a good reference rather than reading through reader reviews on Amazon.com (which are not always valuable.) Also, some books may not be excessively popular and it is more valuable to have a dialog or opinion of a person who is responding to what your specifically need.
Are these types of questions allowed?