I'd do that with a Pivot Table.  

This should help

http://www.cpearson.com/excel/pivots.htm

You could use Excel's advanced filter functionality.  Follow the menu path
Data / Filter / Advanced filter.  Fill out the appropriate information and
ensure to check the unique records only box.  Look up Advanced Filter on
Excel help.

Hope that gives you a start.

Here's a way doing it with advanced filter, assume the data starts in A4
with a header, in for instance G2 put

=AND(A5="AP",COUNTIF($B$5:B5,B5)=1)

leave G1 blank, then apply the filter, select $G$1:$G$2 as the criteria
range and select copy to another location

Hello everyone!

I would like to extract unique records based on a condition. For example,
how to extract unique record from column 'B' when column 'A' has "AP" or any
other desired condition.

The data is as follows:

     A  B
     MI 70056542
     MI 70056543
     AP PATRICK CUDAHY INCORPORATED
     AP PATRICK CUDAHY INCORPORATED
     AP SUGAR CREEK PACKING CO
     AP SUGAR CREEK PACKING CO
     AP VICTORYS KITCHEN
     AP VICTORYS KITCHEN
     AP BRIGHT CHEESE HOUSE
     AP BRIGHT CHEESE HOUSE
     AP CAPPOLA FOODS INC

The final result should look like this:

     C
     PATRICK CUDAHY INCORPORATED
     SUGAR CREEK PACKING CO
     VICTORYS KITCHEN
     BRIGHT CHEESE HOUSE
     CAPPOLA FOODS INC

Thanks
SJ

Try this:

Assume the range of data is A2:B21

Enter this array** formula in C2 and copy down until you get #NUM! errors meaning all uniques have been extracted:

=INDEX(B$2:B$21,SMALL(IF(A$2:A$21="AP",IF(B$2:B$21<>"",IF(MATCH(A$2:A$21&B$2:B$21,A$2:A$21&B$2:B$21,0)=ROW(B$2:B$21)-ROW(B$2)+1,ROW(B$2:B$21)-ROW(B$2)+1))),ROWS($1:1)))

** array formulas *MUST* be entered using the key combination of CTRL,SHIFT,ENTER (not just ENTER)

Biff
 Hello everyone!

 I would like to extract unique records based on a condition. For example, how to extract unique record from column 'B' when column 'A' has "AP" or any other desired condition.

 The data is as follows:

       A  B  
       MI 70056542
       MI 70056543
       AP PATRICK CUDAHY INCORPORATED
       AP PATRICK CUDAHY INCORPORATED
       AP SUGAR CREEK PACKING CO
       AP SUGAR CREEK PACKING CO
       AP VICTORYS KITCHEN
       AP VICTORYS KITCHEN
       AP BRIGHT CHEESE HOUSE
       AP BRIGHT CHEESE HOUSE
       AP CAPPOLA FOODS INC

 The final result should look like this:

       C  
       PATRICK CUDAHY INCORPORATED
       SUGAR CREEK PACKING CO
       VICTORYS KITCHEN
       BRIGHT CHEESE HOUSE
       CAPPOLA FOODS INC

 Thanks
 SJ

Try this:

=IF(ISERR(SMALL(IF(FREQUENCY(IF($A$2:$A$12="AP",MATCH($B$2:$B$12,$B$2:$B$12,0)),MATCH($B$2:$B$12,$B$2:$B$12,0)),ROW(INDIRECT("1:"&ROWS($B$2:$B$12)))),ROWS($1:1))),"",INDEX($B$2:$B$12,SMALL(IF(FREQUENCY(IF($A$2:$A$12="AP",MATCH($B$2:$B$12,$B$2:$B$12,0)),MATCH($B$2:$B$12,$B$2:$B$12,0)),ROW(INDIRECT("1:"&ROWS($B$2:$B$12)))),ROWS($1:1))))

ctrl+shift+enter, not just enter
Drag the Fill Handle to copy as far as needed