Not sure if this is cheeky as not yet an ACC member...
I have a 55/56cm (?) training bike that I'll sell at a snip. £50. I'm 5'11 " too and it's bang on for me. I have a 32" inside leg, if that helps.
It's 12 years old but haven't ridden it for 10 due to injury. I've looked after it in meantime.
As you're looking to start now it's perfect as a 'get me started' road bike that you can muddy up over the winter and it'll take it.
Then when Spring comes you'd have saved up for your sparkling Colnago C50 with Record Carbon (umm??!)...
Apart from the saddle and handlebar tape it's in good nick. I'd be happy to replace them for a wee bit extra, or easy enough to do yourself.
Spec:
Basic, reliable steel road frame with mudguard eyelets, silver with blue flashes. Steel/chromed forks.
Mavic Open 4 CD rims, 36 spoke, Chorus 7 speed hubs. Hutchinson punture-proof training tyres.
Non indexed Chorus gears, shifters on down-tube.
Shimano Exage brakes and chainet.
Regal saddle (comfy but a bit knackered)
Look entry-level clipless pedals.
Altogether a basic, solid package that'd get you started and on the road to bigger things.
Will get a photo up if this sounds interesting.N.