The easiest way to find that is to open a Bible, and look at the cross references in the margins. Prophecy given will usually have a cross reference to a passage where it was fulfilled (for example, the promise of Isaac to Abraham). Likewise, fulfilled prophesies will have a cross reference to the passage where the prophecy was given.
There are also Scriptures in the New Testament that will pinpoint an event and say that it is a fulfillment of an Old Testament prophecy. Like this, for example: Mat 27:9 Then was fulfilled what was spoken by Jeremiah the prophet...
That is if you are looking for things in Scripture, like the promise of the Messiah and it's fulfillment.
If you are looking for something in more recent times, it would be Israel becoming a nation for the second time in 1948, the six day war, the re-taking of Jerusalem...
Keyword search fulfilled prophecy, and you will get tons of websites.