So, I got passed the part where you are in the back of a truck, dropped off in a sandstorm, second town, etc.

I had to bring in a weapons barge flying a UFLL flag, and protect the guy who was on it.

I did that mission

Town is now in a huge war, etc.

I have NO mission
There are NO extra markers on my map
I CANT take missions from radio towers.

Any fixes? Any ideas what to do? I'm quite annoyed, to say the least.

go back to barge if it still near town and drive it to Mikes Bar. Try going into Mikes bar if you haven't yet.

No you don't drive the barge.
You don't go into Mike's bar.

Your buddy has driven the barge back to Mike's bar and intends to sink it there.

Go onto the barge, back into the wheel room, meet your buddy, things progress from there.

You should have gotten a phone call from him.
Sometimes these are easy to skip by accident, or just plain hard to tell what the hell they are saying especially that Irish guy Frank.

In-Game subtitles on ftw.