>>>I'm trying to write a query of the system tables in my DB where I pass it the id of the table - and what I want to get back is the colid and name of the column that is the primary key for the table.
>>
>>It's not recomended directly query SQl Server system tables. If you're using SQL 2000 see if you can get that info from Information Schema views.
>
>Thanks Sergey - I just did a search in BOL and it returned over a hundered items when seraching for 'Information Schema views'. Can you perhaps narrow the scope of where I should look to find specifically what I am looking for? I appreciate your assistance.

In the BOL index type 'INFORMATION SCHEMA' and you'll get the list of views. Anyway, try this from QA.

USE pubs
SELECT OBJECT_ID( isv.constraint_name) 
	FROM (
SELECT * FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS
	WHERE CONSTRAINT_TYPE = 'PRIMARY KEY' 
		AND table_name = 'titles') isv

BTW, they are located in the master DB and you can view there code source if you've to dig into system tables.