There is no item-level permissions  in a document  library.

What about:
(a) A filtered view using ME to leave out all other items? It will not
secure the docs rather it will just not show them on the screen (like
audience)
(b) Using Lists as a base and saving docs as attachments? you will get the
full list  security but may not be able to use doc attributes and other doc
lib specific features.
(c) or any other custom coded solution if that's an option.

I know when you upload a document  to a document library  and you open
the document from the site, in the task pane that appears on the right
you have a lot of permission locking features in Word. I am not sure
if there is a do not allow read  access, but I know that you can define
sections that people can edit, and you can define the document read
only based on the users  that have access  to that document library.

The other way around this is to simply purchase Microsofts Information
Rights Management server. Then, you can set  all kinds of privledges
on each document regardless of what the users rights are to the
document library.