One I came up with while doodling:
The Complete Idiot’s Guide to The Anglo-Saxon Chronicle
And the pic I made 
About 45kB.
One that struck me as funny (apologies if someone has already thought of it):
“The complete idiot’s guide to self-esteem”
“The complete idiot’s guide to complete idiocy”
How about “the complete idiot’s guild to internet pornography”
Osip
The Complete Idiot’s Guide For Dummies.
Here’s my link to silliness…
http://www.iantheterrible.com/rambles.cgi?date=1999.12.28
(the complete idiots guide for dummies)
if you go out to rambles you can read my addition to the rambles “John Watson Speaks” (my name is not really John Watson, but if you’re Wonko, it’s an appropriate and more normal sounding pseudonym). It also has a -very- silly story.
I think I did see a “Psychics for Dummies” once. I wonder what the Dummies people were presented in the way of credentials to allow to author to do the book?
WTF?? There’s a GUILD now? Sheesh, I need to keep up with the porn world. 
My husband always gets very annoyed when he sees this one (a real one):
Sex for Dummies
figuring if you’re dumb, you really shouldn’t be reproducing, and you don’t deserve to have orgasms either.
Bigger, so can read the jokes:
http://www.acmecity.com/thematrix/realworld/214/ig.jpg
My brother suggested the Idiot’s Guide to Idiot’s Guides.
-SSB
“Bob for Dummies”
An old joke for those who remember the late and unlamented program Microsoft Bob.
How about:
Breathing for Dummies
The Complete Idiot’s Guide to toilet paper
Idiots’s guide to reading.
Weightlifting for dumbells.
Paperclip for dummies.
Toothpicks for dummies.
Actually, there really is one called “The Complete Idiot’s Guide to Enhancing Self-Esteem.”
a good friend of mine in college had a copy of sex for dummies. it’s pretty well done, i thought. written i think entirely by dr. ruth. granted, it’s not something you can learn completely from a book, but it’ nice to hear another person’s thoughts on the matter.
Damn!
how about
“The Complete Idiot’s Guide to Stealing a Book Series Idea”
“The Dummy’s Guide to Ventriloquists?”
Idiots Guide to Making Frozen Waffles
Idiots guide to Watering Houseplants
Idiots guide to using Tampons
Idiots guide to Brushing Hair
Idiots guide to Picking Toe-Jam
Idiots guide to Scratch-N-Sniff
Idiots guide to Wearing Socks
Idiots guide to Blinking
Complete Idiots guide to Masturbation
I’m on a roll!