I'm nearly as far away from libertarian as one can be, but no - it's not the same as not having laws.
Example: Old (American) West-style "frontier justice" where a bunch of townspeople form a posse or a lynch mob or whatever to right some (real or perceived) wrong.
(edit: I do understand that this is only one possible scenario, and not what all or even many libertarians want)
For an illustration of this, check out the very first scene of the TV series Deadwood. There's a lynch mob outside the sheriff's office, and they want to kill the person in the jail. The sheriff fends them off so he can legally hang him instead.
The creator originally wanted to do a series on ancient Rome, about the birthplace of civilization. The studio wanted a Western. He said, oh, perfect, that works, too.
Edit (since I cannot reply directly, apparently): why is it not credible?
Can I start citing the X-Files or Star Trek? How about a broadcast of the Nancy Grace show?
If the result is the same (the prisoner dies), does it matter whether a legal authority performs the killing, or whether a mob does? I think it does.
You may not agree with the legal authority's process or laws, but at the very least it is written down.
HN hides these links to prevent very quick back-and-forth. Either wait a few minutes or click the 'link' link.
If multiple such groups have the "right" then you have either a coalition state or tribes with warlords, but even that only really changes the level of jurisdiction.
It seems to me that some libertarians try to claim theoretical victory by defining their legal enforcement to be a private contractor or somesuch, but as soon as they do that they've simply re-defined the government to be that private contractor (or whoever is controlling them) instead. There's still a state and still governance, whatever you happen to call that particular rose.