I was hunting around to figure out how to do this, then reverse engineered it on the backend.... so it may not be 100%.  I figured I'd share my findings in case I'm able to help save someone else a bit time.
If you're just looking for a list of reports in the System, you can query Cognos with the following SQL and get it.  I realize the SQL is poorly syntax'd for performance, but the data is so small it's lightning fast anyways.
USE [C10.1.1_ContentStore];
GO
SELECT *
FROM CMOBJNAMES
WHERE CMID in (
            SELECT CMID
              FROM CMOBJECTS
              WHERE CLASSID = (
                        SELECT CLASSID
                        FROM CMCLASSES
                        WHERE NAME = 'report'
                        )
            )
ORDER BY NAME
Hope this saves somebody out there some time.
cheers,
TheCognosDave 
			
			
			
				You can do this via SDK:
http://www-01.ibm.com/support/docview.wss?uid=swg21374788
You can also use the Content Browser tool:
https://www-304.ibm.com/connections/blogs/basupportlink/entry/ibm_cognos_bi_content_manager_browser_diagnostic_tool2?lang=en_us
http://www.ibm.com/developerworks/data/library/techarticle/dm-0808masters/
http://www-01.ibm.com/support/docview.wss?uid=swg24021211
As for doing that manually via SQL - No idea. I tend to use only Cognos provided tools to go in there.
			
			
			
				TheCognosDave,
Thanks for sharing. As I'm new to Cognos, but not to SQL, I tend to feel a little more comfortable right now navigating through the backend. This snippet was helpful, although I had to change CMOBJNAMES to CMOBJNAMES_BASE.
Grim, Thanks for showing the alternative front-end approach.
-Cort
			
			
			
				Ohiocort:  Glad to help man.  I'm the same way ... all the answers I want are in the database somewhere ... it's just the work of reverse engineering a bit to figure out where !  ;D
Grim: thx for the tip !
			
			
			
				NP
Add: I don't know why this slipped my mind either, but you can produce a list of all reports via a quick list report against the Audit package too (If you have an Audit DB setup, which you should!).  ;)