I’ve always found that the best lie is just the truth told ‘unconvincingly’.
I am myself indifferent honest.
Satch
“One careful owner”
“your jobs are safe, we’re going to look after you”
C’mon, it’ll be fun!
Ah yes, that’s one of mine as well. “I didn’t/don’t have a choice” ? Fuck. you.
And then there’s the oxymoron “In my humble opinion…”
Free Downloads
“You may already be a winner.” Just barely possibly true to some some far distant decimal point of chance, but pretty much a lie.
Free anything 
Though not an out-and-out lie, in my experience, “I think we should take a little time off” is an incomplete sentence. The rest of the sentence is always, “… like for the rest of eternity.”
“Satisfaction guaranteed”
“You’re the best in bed” is not always a lie, but it almost always is.
Has this been said?:
“I want to hear your honest opinion.”
I said that to a friend once, and boy, was I sorry. I didn’t want to hear it.
Guess that makes me a liar, too.
A corollary to that would be “To be totally honest…”
“I’ll only put it in a little ways.”
“I am not elsewhere.”
“This is not the [name] I knew.”
The number 1 lie:
The number 2 lie:
“And we’re glad you’re here.”
(Works well substituting “(corporate) headquarters” for “the government.”)
Pinching from Pratchett:
“I’m telling you this as a friend.”
No you aren’t. If you have to prefix/suffix your statement with this phrase, you aren’t really a friend. You aren’t even being convincingly friendly.
“We’ll keep your resume on file.”
Oh, good one. Have you ever tried telling an HR Department, “Well, when I last applied, you said you’d keep my resume on file, why don’t you just pull it?” Wait for the “bluh, bluh, bluhs”.
Yeah, the circular file…
It’s no big deal; it happens to all guys.
“I’m walking out the door this very minute.”
“You can’t miss it.”
“Your doctor’s appointment is at 2 p.m.”
(Then why do I always have to wait until 3:45 to see the man?)