Ok, this is something seeming not easy at all, and pretty difficult to get completely at first… I mean that was for me.
Here is the magical class for that : Mage_Eav_Model_Entity_Attribute_Source_Table
Once you have the attribute object, you have to get its source, and then its options. Like this :
then loop through $options to get the id with the text value.
$seller = $attrs['seller_confirmation'];
$options = $seller->getSource()->getAllOptions();
You have to make sure $seller is a completely loaded attribute magento object (a select attribute, of course)
inversely, you could use
to get the text of a known id value.
$option = $seller->getSource()->getOptionText($id);
That should do it.
PM me if you have problems with this.