But this IMO is a minority of manuals, and very much not true in the case of perl's documentation. Maybe the perldocs can do with some reorganization or better indexing, but the language and numerous examples used make it one of the more friendly documents I've come across.
Most of the questions that get RTFM's are usually from people that have probably just picked up the language but don't want to bother to 'learn' it, just use it right off the bat; this is very typical of homework trolls who just want the program to work to get a good grade in the class but don't care to remember perl in the long run. In most of those cases, RTFM is the right answer, given that the answer they want is right there. But there are a good minority of posts that sometimes will get RTFM answers but the people asking does have a serious question or concern, generally even after scanning the docs. It's sometimes hard to separate out those truely asking for help from the 'do it for me' crowd, so one way to avoid getting a gruff RTFM answer is to make sure that you tell us that you've already glimped through the manual or whatever and can't find what you're looking for. That would tell us that you've done your homework before asking here, and you'll probably get a more thorough answer than typical FAQ pointers used in newsgroups and such.
Dr. Michael K. Neylon - email@example.com || "You've left the lens cap of your mind on again, Pinky" - The Brain