How to transfer an audiobook from my laptop to my PC ( both windows OS )?

I downloaded two audio books on my I phone during a business trip.

The download was completetd but the books couldn't be found on my I phone.

I down loaded the audiobooks on my ( windows7 ) laptop but I cannot sync them to my Phone as I usually sync with my Home PC ( windows 7 ).

Any Idea how to transfer the purchase to my home PC as I tiunes tells me that all puchased items are downloaded already ??