I’m looking for a similar option that exist in Facebook (http://developers.facebook.com/docs/reference/plugins/send/) But for google.
Something like a button that allows people to view a list of their gmail contacts and select some of them and send them a message.
I’ve found friendconnect, which does something similar, but not exactly it. In any case friendconnect will be discontinued on March 1st.
Any ideas?
Your application should probably take care of sending the messages, but if you want to get which contacts a user has, there is an API for it (http://code.google.com/apis/contacts/).
This will of course require the user to trust your site enough to authorize this data exchange.
You should consider requesting this access using OAuth. There is some information about this here (http://code.google.com/apis/contacts/docs/3.0/developers_guide.html#Auth).