Firstly, an important point about secondhand or refurbished laptops: They generally don't come with any guarantee that the battery will hold a charge for very long (if at all). That's no problem if you only intend to use it on the mains supply anyway but you need to add in the price of a new battery if you actually want to be able to use it on the move.
Having got that out of the way, I can thoroughly recommend A C Computer Warehouse as a supplier of refurbished laptops:
http://www.accomputerwarehouse.com/products/computing/laptops-notebooks
I can see no reason why your friend would need Word installed. It would simply be adding an unnecessary expense. There are several equally good free alternative. See my post here for details:
http://www.theanswerbank.co.uk/Technology/Computers/Question1308849.html
(I use OpenOffice on my netbook. It does everything that Microsoft Office does but it makes things easier if you set things up so that it uses Microsoft Office file formats by default. See my second post here:
http://www.theanswerbank.co.uk/Technology/Computers/Question1312233.html ).
As you'll be aware, dongles aren't really suitable for large amounts of internet browsing (because you only get a fairly small amount of data for a relatively large sum of money) but they're probably the only option open to your friend. However it might be worth checking to see whether any of his neighbours are using BT internet services. If so, anyone who subscribes to BT Wi-Fi can connect to the 'public' side of their BT Home Hubs with 500 minutes access per month (which might be enough for a quick daily look at the jobs available online) for a monthly fee of £6.
See here to find out if there's a local hotspot for your friend (or simply use a wi-fi enabled phone to search for a BT signal):
http://btwifi.hotspot-directory.com/
See here to subscribe for £6 per month:
https://my.btwifi.com/selfcare/purchase/chooseProduct.htm
Lastly, it occurs to me that your friend is going to need an email address to use the online jobseeker's service. I recommend GMX:
http://www.gmx.co.uk/