Scouting a club is a new feature in FM12, not in FM11 - unless you are playing that team next. Just click a scout and then 'Add New Assignment' or something similiar, and select 'Next Opposition'.
1. Click on the club
2. Click on matches
3. Find their next match
4. Click on the "-" between the team and it's opposition
5. See "attend" pop up where you clicked
6. Watch the game
that's the only way. Doing this reveals the attributes of all of their players who play in the game.