how to start? i want to play ladder, which is the best farm char? warlock? or still sorc?

Sorc is the best starter as it has teleport.
Warlock is the strongest even with little items.

If you're starting out I think the best Sorc is generally considered as Sorceress.

I did Hammerdin this season and just spammed Travi until I got a few HR's and went from there.

but you should have enigma for warlock right? otherwise sorc is better for farming

Yes, enigma is still the great equalizer.

you think the same is possible to do with warlock? spam travi on hell untill you got HRS?

Warlock echo strike can easily do hell chaos runs with minimal gear investment.

Has blade warp to jump across river of flame

sorc or warlock to farm gear for portal barb

Yeah warlock is 20 times stronger than any hammerdin

You just need insight and spam echoing strike, can even use the ability 'bind demon' and try to bind a demon with cursed to make it your pet so you double your damage

Yeah I think ES is best starter build now and run Trav and Chaos and TZ.