I live in Australia.  I have a friend from Bristol, Tennessee who told
me that oral sexual acts were illigal in Tennessee.  Even between
consenting adults.  I know it's stupid but he is adamant and i want to
prove it.

If that was true it would sure suck.

I believe your friend is behind the times. Although oral sex used to
fall under Tennessee's very strict "crimes against nature" law, the
law was struck down in 1996.

More information may be found here:

http://www.sodomylaws.org/sensibilities/tennessee.htm

I understand that Tennessee's Homosexual Practices Law, which
prohibits sodomy (including oral sex, etc.). is still on the books,
but it has been declared unconstitutional by a higher state court,
which was confirmed by the state's supreme court's refusing to review
the case.
Scroll down to Tennesse on this site, and if you want, click on the
case and read the whole thing.
http://www.sodomylaws.org/legal.htm

I suppose that since the law is still on the books, the act is
technically still illegal, but it is unlikely that anyone would now be
booked for it.

There are several sites such a bizarre laws, dumblaws that report that
oral sex is illegal in Tennessee, but that is only half the story.

This is a free comment.

Whoops, Pinkfreud snuck in her comment while I was writing.  Same reference.

THANKS SO MUCH GUYS - I ONLY POSTED AN HOUR AGO.  VERY IMPRESSED.

In the US, these types of laws are called "Blue Laws" --laws that are
outdated and have somehow escaped being purged from each state's
actual "Criminal Codes" statutes.

Here's a link to give you an idea of just how weird (and outdated)
some of these laws are:

DUMB LAWS
http://www.dumb.com/laws.htm

My personal favorite is in Kentucky:

"...  By law, anyone who has been drinking is "sober" until he or she
"cannot hold onto the ground".  ..."

I got coffee all over the monitor whan I read that!  ;-)

Cynthia, we in New England use Blue Laws to refer to the (mostly
antiquated, but not quite) rules that govern what stores have to close
on Sundays. Supposedly the term is from Blood Laws, as the original
laws required a physical punishment that drew blood, e.g., whipping or
pillorying (what the rest of the country would call "being put in
stocks").

What I find comical about some of these laws is they require liquor
stores to be closed on Sunday but allow liquor sales from grocery and
convenience stores. What were those Puritans thinking?

To be honest, I sort of liked having most stores closed on Sundays
(they still do this in much of Spain). It forced the working class to
have a day off to spend with the family. Of course in a lot of places
you weren't allowed to get lucky, much less freaky, on your day off.

Wow, although I do recall "blue laws" in Seattle: 

Cannot buy alcohol on Sunday.
Cannot buy meat on Sunday. (both repealed)

There were others not associated with Sunday:

Cannot move from bar to table with drink in hand, bartender must move
it. (and others)

I guess I was referring to the more general Colonial meaning, wherein
the Blue Laws attempt to correct inappropriate behavior of any kind,
on any day, although certainly Sunday was the major day that perfect
behavior was expected!

Colonial Massachusetts - Blue Laws - Personal Conduct Regulation
http://www.u-s-history.com/pages/h1164.html

Political Dictionary
http://www.people.virginia.edu/~rmf8a/gaskell/poldict.htm
..."Blue Laws. The strict Sabbatarian laws of colonial times,
especially in Connecticut. The term is sometimes used to designate
obnoxious modern laws in the interest of religion and morality..."

I saw this:

Adultery, abuse could cost in divorce (Tennessee link)
http://www.tennessean.com/government/archives/05/03/67932663.shtml
..."''It's harebrained,'' said Nashville attorney John Hollins Sr.,
who likened it to the past when adulterers could be arrested under the
''blue laws'' ? religious laws regulating moral conduct..."

[ the above reminded me of the term my Mom used to refer to ]

However, after a search on "Blue Laws," the most common meaning by
far, unbeknownst to me prior to this, is the Sunday prohibitions:

BLUE LAWS
http://college.hmco.com/history/readerscomp/rcah/html/ah_011100_bluelaws.htm

In any event, they are certainly DUMB!