Best way to create tags under new EntryModel?
To relate the tags, all you'd have to do is feed the entry's tag field an array containing tag IDs.

So, after creating (or finding existing) tags, you should end up with an array with one or more tag IDs.

Then, if it's a new entry, you would do:

$myTagIds = array(1,2,3,4); // your tag IDs
$entry = new EntryModel();
$entry-&gt;setContentFromPost(array(
    // ...
    'tagFieldHandle' =&gt; $myTagIds,
));

craft()-&gt;entries-&gt;saveEntry($entry);