Why is there a lack of resources for citing MLA, APA, etc. for students?

i just do not understand it because teachers ign papers knowing that the citation directions are so hard to find on the internet especially for unique sources. teachers cannot expect all students to go buy the handbook in public schools. why do they think it is logical?! the good ones i know provide the info. for students and are available for questions about citing sources. but grr there are just so many terrible teachers these days!!!