Create distribution list with non domain users

Hello,

I have been asked to create several Distribution Lists in Exchange 2010 for people with external email addresses. I understand that I can create a mail enabled contact with the external email address and have done this with one of the groups.

The thing I do not care for is that all these contacts are listed with all the users in Active Directory. I am looking for someway that this could be done more neatly. Is there someway that I could create a new OU and place all these external contacts in there to segragate them from the users.

Just trying to keep this clean looking and asking for suggestions.

Thank you,

Tom