Where are the others?

Still trawling through the New Testament in my nightly readings of a few chapters at a time... and was just wondering:

What happened to all those disciples who were sent out by Jesus personally? Yeah, I know what HAPPENED to them (many were martyred), but why don't we hear a lot about them in the New Testament? It's mostly just Paul going on to the churches HE planted, but what was happening with the other guys, the other 11 and the larger group that followed from whom they were chosen?

So some of them wrote a book here and there of the New Testament, and John saw visions on his prison island - but while Paul's going on about the church here, the church there - where are the others?

They're pretty quiet about what they're up to. They're likely working among the Jews, which may not be as dramatic as revolutionizing the Gentile's lives, but still....

Just got me wondering. But I'm only up to Hebrews, so maybe I'll still find them somewhere.