Are there any examples of PCFs written about how to find flag patterns?

Are there any books focusig on easy scans and wirting PCFs?

You may wish to review the following for information on pattern recognition in TC2000 (focusing on topics mentioning flags, wedges and pennants).

Falling wedge
Cup with a handle formation
PCF for cup with a handle
Scanning for Chart Patterns
Scanning for Stocks Printing a Double or Triple Bottom
PCFs for pennants and flags
PCF's for Triangles
Does TeleChart support Elliott Wave indicators?
Double top/bottom trend
Finding Double Tops and Double Bottoms
CUP AND HANDLE AGAIN
Finding Continuation Triangles And Wedges With Telechart
Cup & Handle PCF
Double tops and bottoms
Flag wedge and pennant pcf
05/01/2012 Webinar: Trading the Flag and Pennant Patterns
Head and shoulders
TC 2000 Bull flags, Bear Flags
PCF for rounded bottom trading

That said, I personally do not think complex pattern recognition is practical in TC2000 using formulas and Scans.

They are at the very least beyond my abilities to help you create without a specific unambiguous objective definition of what you are attempting to identify. It can't be an I know it when I see it type of definition or be based entirely on an image.

This is true of pattern recognition in general with the exception of fixed size candlestick patterns, which are fairly straightforward as long as the pattern is well defined. The first topic referenced in the post has formulas for candlestick patterns.

The following topic has has Condition Formulas to identify candlestick patterns in TC2000.

Boolean PCFs for Candlestick Patterns

There really isn't a book of which I am aware on creating PCFs and EasyScans.

The PCF Formula Descriptions topic lists all of the syntax which is valid in the Personal Criteria Formula Language and the Handy PCF example formulas to help you learn the syntax of PCFs! topic has basic examples of this syntax in use.

I'm not quite sure how useful it would be to anybody else, but the Personal Criteria Formulas topic has a list of topics I find useful.

You are generally better off not creating formulas unless absolutely necessary. So I would check out the following videos as well.

Create Conditions from Your Chart (5:25)
Building a Scan with Multiple Conditions (7:29)
Creating Conditions from Your Charts (57:04)
Writing Custom Conditions: The Basics (40:36)
Writing Custom Condtions: Useful Examples (51:30)