I want integrate following apis in my website,
1. Yahoo BBAuth
2. Google OAuth
3. Live ID Delegated Authentication
4. Facebook Connect

Does these facilities enable me to get their email addresses as i cant find any mention of email address of the logged user in the API documentations.

I can answer for Google OAuth: no. If you want to have the user's email address, then you can implement ClientLogin instead. However, I can't imagine that users are willing to supply their google login information to you.

Don't know about the other's.

No they wont. When they will click on the icons, they will be redirected to the yahoo, gmail or live. Then the respective party will land the client back to my website with some unique identifier token. With that token i can call their webservices for fetching information. What i want to know that is there anyway that i can fetch their email address through it. If someone has done that before.

You can look at the website evri.com. They have integrated the different logins.

Google has no request for retrieving the username/email.