たところだ

たところだ means "have just done": the action finished a moment ago and you're at the point right after it. It follows the た-form of a verb. In polite speech だ becomes です.

いま今, たったいまたった今 and さっき fit with it, because they point to the last few minutes.

たところ or たばかり

たところ is about the moment: seconds or minutes ago. たばかり is about how it feels to the speaker, so it can cover days or months that seem recent.

• × 先月日本に来たところです → 先月日本に来たばかりです

ところ after other forms

The form in front of ところだ says where you are in the action. Each of these is a grammar point of its own.