O_5 - Mars Attacks
As for my own,
PJ_1 Everything I needed to know about going from cynicism to belief, I learned from David Duchovny. (There are two possible answers)
is still out there.
PJ_2 lost4life was correct with What’s up, Tiger Lily?
Recap of others (except Homebrew’s) that have not received an answer (unconfirmed answers are not included here, so if someone was wrong, speak up).
I_L_1 “Everything I needed to know about Bill Cosby, I learned from John Cusack”
I_L_2 “Everythng I needed to know about Beluga Caviar, I learned from Hugh Grant”
I_L_7 “Everything I needed to know about drive by shootings, I learned from Diane Keaton”
L4L-4 Everything I know about cool footwear, I learned from Brad Pitt.
SA_1: Everything I know about railroad tracks I learned from Vin Diesel.
SA_2: Everything I know about bull whips I learned from Marcello Mastroianni.
SA_3: Everything I know about tattoos I learned from Michael J. Pollard.
O-1 Everything I needed to know about really big guns, I learned from Charlie Chaplin.
O-2 Everything I needed to know about pornographic web sites, I learned from Sylvester Stallone.
O-4 Everything I needed to know about being a news anchor I learned from Stockard Channing.
O-7 Everything I needed to know about being president of the United States I learned from Dan Hedaya
O-10 Everything I needed to know about being president of the United States I learned from Jon Voight
Z_3 (alternate)
Z_6 “Everything I needed to know about being a news anchor, I learned from William Hurt.” - Broadcast News
Z_10 “Everything I needed to know about surveillance, I learned from Roy Scheider.” The French Connection
Z_11 (alternate) - Enemy of the State
Z_14 “Everything I needed to know about the legal profession, I learned from Paul Newman.” - The Verdict?
HB_6 “Everything I needed to know about having a conversation (but not with a pirate), I learned from Wallace Shawn” - My Dinner with Andre
New one :
PJ_3 Everything I needed to know about junior high, I learned from Heather Matarazzo.
That this thread, under God shall have a new birth of freedom, and that movie trivia of the people, by the people, for the people shall not perish from the earth.
I_L_13 “Everything I needed to know about the hands of the rain, I learned from Michael Caine”
HB_6 My Dinner with Andre is correct.
O-7 Everything I needed to know about being president of the United States I learned from Dan Hedaya
Dick
O-10 Everything I needed to know about being president of the United States I learned from Jon Voight
Pearl Harbor?
PJ_3 Everything I needed to know about junior high, I learned from Heather Matarazzo
The Dollhouse?
I_L_7 "Everything I needed to know about drive by shootings, I learned from Diane Keaton
The Godfather?
HB_5 "Everything I needed to know about model building, I learned from Alec Baldwin
This one’s so simple I missed it entirely…Beetlejuice!
SA_3: Everything I know about tattoos I learned from Michael J. Pollard. “Bonnie and Clyde”
Close enough - full title is Welcome to the Dollhouse.
Beetlejuice is correct.
Is I_L_13 The Cider House Rules?
Nope.
HB_7 “Everything I needed to know about flea-markets, I learned from Corey Haim.”
O7 and 010 are correct.
These are all correct. Sorry for the delay. Had a fried modem as the result of a lightning strike in my yard. No further damage except a tree got its bark blown off. Tree’s still there but probably needs to be taken down. I spent the day dealing with the new modem. Just now got back on here. Damn, I miss this place bad when I’m not here. Just over 24 hours of no internet. I’m as dependent on it as I am food and shelter! 
BTW, I’m not sure on the other Z_3, but figured if somebody mentioned one they knew Gere played trumpet in it would jog my memory. Did he play any in “Chicago”? I saw it less than three months ago and can’t recall. How did that get Picture of thje Year?
Hannah and her Sisters
“Everything I wanted to know about garbage, I learned from Martin Sheen.”
I_L_14 “Everything I needed to know about lakes, I learned from Anna Paquin”
I_L: Fly Away Home
I_L 14, that is.
Nope.
I_L_15 “Everything I needed to know about having a gay boyfriend, I learned from Julia Roberts”
I was right about Hannah and her Sisters, though, wasn’t I?
I_L_15 - My Best Friends Wedding?
"Everything I needed to know about Salvage Operations, I learned from Gabriel Byrne.