Powershell script to get all user profiles with specific email address

Hello,

Please help me. I need a powershell script which can do the following things.

1.       List of all sharepoint user profiles with email address spadmin@xxxx.com
2.       List of all FBA user profiles with email address  spadmin@xxxx.com
3.      List of all Pending Access Requests

Any help is much appreciated. Thanks.

chirag