I've had my car a year and am looking at what diagnostics options I have and it is becoming blatantly apparent that I do not know my FORscan or my IDS from my elbow. What is available and what are the differences in terms of capability/required hardware etc?

I come from a late Saab so what I know is GM based. For those who are familiar with GMs ecosystem I used to use one of these alongside a couple of different bits of software, GDS2 could do all the standard reading/clearing that an ODBII adaptor but with model specific info and test procedures to monitor sensor outputs. It could also initiate various test procedures. For example, at one point the self levelling sensor in my car broke, I got my mechanic to replace it but their standard diagnostics couldn't initialise it (a fairly simple procedure involving having the car unloaded on the ground and a base reading stored). GDS2 did this for me which paid for the VXdiag in one go as I would have needed to pay a GM specialist ~£90 otherwise. Above GDS2, there is GlobalTIS which has dealer level access to security access and can code keys and modules. Both of these could be used under license from GM on a daily/monthly rental basis. 

What are the Ford equivalents?

I see FORscan looks to be popular and can run over relatively cheap scanners as well as the Ford version of the VXDiag Nano that I am familiar with.

I see the adaptor I've linked is also compatible with IDS, this looks to be Ford's official software and probably equivalent to the subscription based GM options I mention above.

So where does FDRS fit in?

 

Secondly, any recommendations for workshop manuals? I see Haynes have this  and there is also repairbooks.co.uk.

 

Probably better to repost all of this in the FOCUS forum. Provided that you actually do live in the UK, and not North America.

https://www.fordownersclub.com/forums/forum/2-ford-focus-club/

Thanks for the heads up, will do. I am in the UK.