Welcome, Ian.
DO join your local M E club. Before ordering your lathe, as already said, think about bthe largest work that you will want to turn, in terms of both and diameter and length.
Then buy one a little bit larger! There is no perfect lathe, just ones that suit most of your purposess
The modern lathes are likely to be geared head, rather than belt driven. Gears can be a bit noisier, and don't slip if you have a pile up. A lathe such as a Chester Craftsman will be a belt driven (Warco don't sell their equivalent, the BH600, any more) Mine is another clone, no longer available, an Engineers ToolRoom BL12 -24, Metric, but with dual dials..
Speeds are changed on belt driven lathes by moving the belts over the pulleys. More modern machines vary speed electronically.
A Nnorton gearbox makes setting up feeds or thread pitches much easier than selecting the best set of changewheels. Such a machine may well have Power cross Feed built in. This can be a useful feature.
You might be able to find secondhand BH600 in good condition – they came in Imperial or Metric vesrions. The Craftsman is only Metric, but the current ones have DRO, so can read in either Metric or Imperial.
Upto 1/2" you should be able to make most threads using Taps and Dies..
Unless you are cutting hardened steel, High Speed Steel should suffice for most work, in my opinion.
My favourite is a tangential turning tool. The commercial version is the Diamond Turning Tool, sold by Eccentric Engineering.
Hope that all this a little help. You will gets lots of help on here, so keep in contact.
Howard