i need ideas on why tape recording someone without their knowledge is wrong and immoral.

I believe this falls into the "right to privacy" beliefs in our country. Here are some webpages with ideas:

http://www.law.umkc.edu/faculty/projects/ftrials/conlaw/rightofprivacy.html

http://topics.law.cornell.edu/wex/privacy

http://www.privacilla.org/fundamentals/privacyright.html

You can find more by Googling right to privacy.