If you're only just 50, personally, I wouldn't recommend trying to get the books (or at least the second one) unless you're really dedicated and ready for the challenge. The Artisan gear is easy to get now, not even sure you really need the first master books for anything besides glamour at this point.

I recall, back before I installed any expansions, capped at 50 and trying this stuff out. Getting the mastercraft I books was difficult, but manageable. Trying to go for the second was daunting.

Although, come to think of it, that might mostly have also been just because of the demimateria needed along the way.