E-mails dissapeared from webmail, didn't show up in Outlook!

I recently (yesterday) put my webmail account and Outlook 2007 together. I was really excited, taking one sub-folder at a time, moving it into the main webmail inbox, and then going to Outlook and pressing Send/Receive. Most of the time, the e-mails came into Outlook beautifully. But after a few go rounds, I repeating the process, hit send/receive and nothing happened.
The e-mails didn't show up in my Outlook account.
I thought nothing of it, figured I'd try again the next day, and when I came back to my computer BOTH webmail and Outlook don't contain these messages. Not in the deletes, not in any folders; I tried doing a search in both and nothing came up. The e-mails I was trying to send are just gone from both Outlook and webmail.
The e-mails were very important and I'm desperate to recover them.
Since this is long, I'll try to make a short list of what happened:

1. Sent webmail e-mail to Outlook 2007 with success, (I had also figured out how to stop Outlook from automatic deleting my webmail after the successful download of messages.) I was on top of the world.
2. Moved yet another message block from a webmail subfolder to my webmail inbox
3. Clicked Send/Receive in Outlook, got pop up box telling me the transfer was successful.
4. Noted there were NO new messages in my Outlook Inbox.
5. Gave up, slept.
6. Came back to Outlook, this time messages* (*of all sizes, with and without attachments, and from a wide range of dates) transferred successfully. After a few more transfers, the above problem resurfaced. Nothing was showing up in my Outlook Inbox
7. When I closed and reopened Office 2007 and webmail, the messages I had attempted to send were gone from both.

I've trolled around the internet for hours and hours without luck, Please Help!!!

Thanks so much,
-D