Here is insight on mailing and working with agencies. First. I would NOT send photos through email. It is unprofessional. It is more professional to send your compcard. Mainly because:
1. It shows you have already been in front of the camera and have put together a nice marketing compcard for the agency to use.
2. It shows you are ready to go, right now, to a casting, you don't need to "still make a compcard."
3. It shows you are serious about modeling. You have your marketing tools and you know what you're doing.