You will get on famously with that book [Peter Reinhart's Bread Baker's
Apprentice]. It's probably the best yet written. It doesn't much matter
what flour you use for the starter, but use strong bread flour when it
comes to the loaf itself. The issue about water etc is that the starter is
a living thing (the yeast) and any additives, particularly chlorine are
likely to harm the yeast. Same comment for bleached and bromated flour. The
yeast may survive but why take the chance? The temperature of the starter
matters less as it gets more mature. Room temperature is fine, as long as
you don't live in an unheated house in an Alaskan winter! Room temp
normally means around 14 - 16 degrees Celsius and that's fine, just slower
to 'work' after feeding, when you are preparing to use it for baking. The
worst problem is reading too much - get on and do it!
Brian