can someone point me to any info about how to organize a signature-ad campaign, I mean how is done exactly, how are the posts counted and and rewards calculated etc. ?
There's no 'how to: Signature Campaign', if that's what you are searching for.
Most things are either no-brainers or you learn them along the way, and you develope your own routines/process.
Are there any automatic counters?
Some campaigns (YoBit, Bitmixer, bit-x) utilize bots for their signature campaigns/post counting, others don't (because a bot IMO can't fully replace a campaign manager).
As an answer to your question, yes, there are bots which automatically count posts.