Here are a few quotes to start together with a whole host of resources at the end of the page to put some zest in your presentation .
"Be sincere, be brief, be seated"
Franklin D. Roseveld
"It takes one hour of preparation for each minute of presentation time."
Wayne Burgraff
Dave Carey "There are always three speeches, for every one you actually gave. The one you practiced, the one you gave, and the one you wish you gave."
Dale Carnegie "No one can remember more than three points."
Philip Crosby "The audience only pays attention as long as you know where you are going."
Philip Crosby "Ask yourself, ''If I had only sixty seconds on the stage, what would I absolutely have to say to get my message across."
Jeff Dewar "No one ever complains about a speech being too short!"
Ira Hayes "Humor heals the heckler."
Gerald C. Meyers "Ask a heckler to identify himself and his company. They usually prefer to be anonymous."
Judy Moreo "I use many props. The props act as cue cards reminding me of what to say next."
Tom Ogden and a very clever bit of advice to finish.
"The simplest way to customize is to phone members of the audience in advance and ask them what they expect from your session and why they expect it. Then use their quotes throughout your presentation."
Alan Pease
-- Wess Roberts
Where to get quotations for presentations?
Yahoo's list of quotation sites
The brainy quote
Famousquotations.com
The Quotations page
Quoteland.com
Quotationreference.com
Famous quotes and quotations
Quotelady.com
Great-Quotes.com
Quotation resources by about.com
Business-related
Dr. Gabriel Robins' "Good quotations by famous people"
World's best quotes in 1-10 words