Hi people,
I apologize for the delay replying to this thread. We have definitely heard from several of you that this is an important feature to include in Adobe Send; we're continuing to work on making Adobe Send the best service it can be for sending large files, and the ability to access/remember contacts is part of our discussion. For what it's worth, you can always use Adobe Send through the free Adobe Reader software; if you log in through Adobe Reader, you can have access to your local address book while sending your files. Here's some more info on that front. We're also going to be releasing a plugin for Microsoft Outlook (2010 and 2013) sometime in the next few weeks, so if you're on Windows that will be another easy way to use Adobe Send in conjunction with your existing address book.
Let me know if I can offer any more information or assistance! Thanks for posting.
Best regards,
Rebecca