When I post or trade a link I first consider the following;
'Is this web site going to be of value to someone who visits my website'.
Frankly, I do not care if the site has a Page Rank of '0' or whether or not it has been indexed by Google.
I see it this way... if it is a well designed site, with great images, content or information it will (eventually) do well in the search engines on it's own merit -- in due time.
It's always best to post/trade links with websites for the sake of your visitors, not search engines.
This type of linking can only be done manually.
Although it can be a tedious process I have seen this linking approach help to achieve a more stable SERP during algo changes circa Sept 2005.