I have a website on which it is possible to register and create an account by filling a form. In addition, to this I want to give a feature where visitors can log in with other a/cs such as Gmail, Yahoo, AOL, Hotmail and verizon.net. My current programmer has been able to do log in with Gmail, AOL and Hotmail. However, the script for Yahoo and verizon is not working.

An additional feature is that users should be able to import their contacts in these accounts and send invites to them. This feature is working only for gmail. It is not working for AOL and hotmail.

I want a programmer who is experienced in this field and can do log in with verizon and yahoo and also import contacts for Yahoo, AOL, Hotmail and verizon.net.

Please bid with samples of websites where you have already done this.