In one episode, I remember George Constanza commenting on the Internet
saying that you could find anything on it.  However, I can't find the
quotation anywhere.  I vaguely remember the quotation being about
devil worshippers wanting to find amputees, though I am *extremely*
uncertain of this.  I need to find the exact quote along with the
episode number and title.  This is for a book I am writing.

I did several searches at the Seinfeld script archive,
http://www.stanthecaddy.com/seinfeld-scripts.html and was unable to
find a quote from George similar to what you are looking for.  Maybe
you will have better luck.

-THV

I did find a quote from the episode The Yada Yada mentioning the internet,
"I gotta get on that Internet. I'm late on everything." 
- Jerry, in "The Yada Yada" Episode 153

I also found George mentioning amputees,
Kramer:  "George, get a penthouse forum".
George:  "I'm NOT gett'n a penthouse forum".
Kramer:  "Wait no, that'll make great dinner conversation".
             "We'll read the letter's at the table".
George:  "Ah, that's nice".
Kramer:   "Come on  what, you ever read one of these"  ?
George:  " It's not real. there all made up".
Kramer:   " Ooooooh it's real alright".
George:  "Well then you know, there's an usually number of people     
               having sex with amputee's".
- George and Kramer "The Dinner Party" Episode 77


Episode guides:
http://www.tvtome.com/tvtome/servlet/EpisodeGuideServlet/showid-112/
http://www.stanthecaddy.com/seinfeld-episode-guide.html

This site let's you search the scripts for keywords through google's
search engine. I searched for amputees, devil, internet and web. Web
yields one line from a a former girlfriend of Jerry's, Nina mentioning
it's called the world wide web now, you can email anyone.
http://www.seinfeldscripts.com

My turn: All I could find were these quotes:

Jerry says, on the Yadda Yadda Episode: 
?I gotta get on that internet. I'm late on everything?
http://tvsothertenpercent.tripod.com/seinfeld.html


From The Butter Shave Epsiode , Kramer says : Did you see Bania's set
last night? 'Cause I read on the Internet he killed.
http://www.seinfeldscripts.com/TheButterShave.htm

Hi hanapin,

I've watched every episode at least 2 times, and if memory serves me
right I have a feeling it was Kramer who said that about the Internet.

Although I can't find that either.  I do remember the comment.  (still
searching for you...)

Best regards,
tlspiegel

Thanks for everyone who's made a comment, especially tlspiegel who's
said the he/she remembers it from the show.  It's given me some
glimmer of hope that we can actually find it!  Do you remember
anything else about it?  Which show it was?  What context it was used
in?

Thanks,
Hanapin

I think you're thinking of "The Serenity Now," Episode 158.

George: Well, I got just the thing to cheer you up. A computer! Huh?
We can check porn, and stock quotes.

(and later)

George: I'll tell you what's insane: the price that I could get you
on a new desktop computer.
Elaine: I am not buying a computer from you.
George: There's porn.
Elaine: (Pausing) Even so.
George: Damn it!

http://www.stanthecaddy.com/the-serenity-now-script.html