@MartynRich - Good to hear from you Martyn, glad to hear your still making vibes. I'm with
@Boydie here, I find Studio One is really easy to use and a lot of the things which can put people off is pretty easy, and more importantly well documented, I know it aint cheap, but they do a monthly subscription version called Sphere which will do you for life, and it includes everything they do, including instruments and all their plugins...
As for free instruments, I can't say but I remember TAL doing something free, other good cheap VSTi's (Virtual Instruments) are from Cherry, I have a Polymoog emu and it's very capable.
You mentioned Spitfire, they are also very good, I'm using them on a single I'm producing for someone at the moment, so it doesn't always man cheap is bad, it normally menas that you can't do as much tweaking, for example there is a VSTi called Garritan CFX, a very good grand piano, there is a lite version for about 80 quid and a full version for about 150, apart for the insane number of sample per note, there are so many tweaks one can make that it's more likely that you'll balls up the sound rather than making it sound better, so don't boiterh spend huge wads. Spitfire is fine, the Mrs Mills, and Felt piano all sound great.
Look forward to hearing your stuff Martyn
Rich