I know there is a list of games that are excluded when you share a library on steam, but I was wondering if there is also a way to exclude some additional games?
If you setup the account you're sharing with as a child account you will be able to select which games it can access from the parental settings.
According to a FAQ put together on the Steam Family Sharing group on Steam, no there is no way to manually select games that you do not share with the account you are sharing with. Meaning the only games that are restricted from sharing are of course the ones that are restricted by default.
Source: Family Sharing FAQ
You need to activate Family Mode and then one by one remove games you dont want to show (or other way around if different default setting turned on).
Cause I wasnt launching Steam for half month or so, here is Internet for the win: http://www.rosary.catholic.edu.au/__files/f/5062/Factsheet_Parents_Steam.pdf page 3.
P.S, never was thinking I'll say thanks to Catholic educational school/web-site
No, when sharing a library, the whole content is available for the person you are sharing it with.