RNG RNG... Haha, its all about building op slowely if ur starting new, for example:
Get a tal sorc using nova, or mavina zon using exploding arrow + freezing arrow is great to start out with. Hell cows is a good place to find highrunes, dont forget u can downgrade runes for free! Start killing less difficult bosses to build up ur wealth, Act bosses + Chests from Fragment sets is a nice way to start farming/getting items. A smiter is awesome to do dreamlands ( Cheap+effective ). Charged Strike zon is awesome as well, but they are expensive compared to a smiter. Another great char to farm ur way up to is a Amazon using Frostfire ( found from Chuthulu ). But then again, drops can be so so so random, u gotta have some luck as well ! Also take a look in the wiki for some great builds!