ってば / ったら

ってば and ったら go on the end of something you have already said and are saying again, louder: "I told you!", "I said…!". They follow the plain form, so a noun or な-adjective takes だ in front. Both are casual speech only.

For repeating yourself, ってば is the usual one. It also goes after a word that calls for attention, when the first call was ignored.

After a person: "honestly, that…"

After a name or a word for a person, ったら and ってば mark them as the one you are complaining about, and the complaint follows. Here ったら is the more common of the two, and it can be fond rather than cross, the way you grumble about family. ってば sounds harder.

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Both belong to talk among family and close friends, and you hear them a lot in anime and drama. In polite speech or to someone above you they sound rude.

This ったら is not the conditional たら ("if", "when"), and not the ったら that says something is beyond words. Those are separate points.