I've just been given a singer 447 sewing machine. I have threaded top and bobbin but the top thread is not looping/ catching the bobbin thread. It doesn't bring the bobbin thread up, at all?

SOURCE: Singer Touch & Sew won't loop bobbin thread

I believe you have a broken gear. These are difficult to repair on your own.

SOURCE: Singer CG 550 Top thread keeps wraping around the bobbin and jam

Have you checked the top thread is correctly placed in the spring of the bobbin case?

SOURCE: Sewing Machine (brother XL 3200)

You may have the bobbin case in wrong.  I have this machine, and I know that it is really easy to put the bobbin case in wrong.  Try taking it out and making sure that the little stop is in the front and it is seated down in there and able to wiggle back and forth.  My experience with this machine, until the other day when my cat knocked mine off the table and knocked something out of alignment, is that it just works.  Any time mine hasn't worked, it has either been dirty, needing oil, threaded wrong or the bobbin case wasn't seated right.  In other words, it has always been my fault.

SOURCE: Singer 457 Zig Zag Sewing Machine not catching bobbin thread.

There are manuals avilable online to purchase for the singer machines, SOrry I was not able to locate a site that has them for free.
.... http://sewingonline.co.uk/singer-manuals.html

SOURCE: Singer Sewing Machine model 9224. Bobbin thread

If you turn the handwheel, can you see a metal ring rotating around the outer edge of the bobbin case? If not rotating, broken gear or timing belt off.
If that ring is turning, remove the needle plate and bobbin case. As this ring now rotates, you will a finger on the ring that will pass behind the needle from right to left and it should catch the thread from the eye of the needle. If this finger, the "hook" passes above the eye, you have a timing problem.

Let me know.