They come to one of the cities you visit and meet you outside. Saying stuff like, "You'll pay for what you've done." I've found them pretty tough to beat. All 2-handers? Why are they after you and why don't the guards do anything to stop them?

if you search thier bodies you'll find a note from who hired/sent them

somebody sicced them on you. you stole something and killed someone and the offended parties put a hit out on you. one of the thugs will have a contract on them.

I think what you're thinking of are the mercenaries that NPC's will occasionally hire if you commit crimes against them (sometimes even if they don't witness it it seems O.o). If you check the bodies, one of them should have a note that says who hired them.

I'm pretty sure they don't come after you until you try to kill a CPU that isn't supposed to die. Because I did that on PC and I got the bandits on my ass, but I didn't do that on the Xbox, so I wasn't hunted down. Think hard, did you attack a CPU that crouched and wouldn't die?

the letter i found on one of the 3 that came after me was from anise. yet, why would she put a bounty on me before i defended myself and snuffed her?

These guys were more challenging then the Dark Brotherhood assasin. In fact, I never beat them early on, just ran after getting pummeled two or three times even inside cities.

Not atall.

System is pretty bugged, kids can send them after you for steeling an aple and similar stupidity. the idea is nice but should be filtered against value of items, how wealthy they are an beggar can not afford to hire thugs and how much they like you.

Sometimes even after you've killed them. They can put bounties on you from the dead

There is a reason why the guards didn't help my Khajiit character named Onyx.

http://www.skyrimnexus.com/imageshare/images/649591-1323710401.jpg

you must havec done something serious.

I got some of those and dark brotherhood assassins after I desecrated a shrine to peyrite. also made enemies of the thalmor because after they got attacked by bandits, I took an armor from the body of a fallen thalmor (I was on their side for that fight, but dead is dead, and wasting an elven armor would have been a shame. clearly they saw things differently...)

but in the early game, I was never hunted down. but I never steal or kill innocents and I help everyone .... except Peyrite worshipers and canibals ....

How do you desecrate a shrine? Take the money and stuff from the offering area?

Is that the old lady in the hut or the vampire chick?

The old lady only turns violent if you steal or trespass. The vampire chick you have to assult or tresspass to get her to attack you.

People send thugs after you if you killed them, or stole from them.

This happens a lot if someone catches you stealing from them or just stealing from them in general. Also killing someone in front of people and not going to jail/paying off your bounty for it will also have a witness send Hired Thugs after you. Not bandits.