Driver's Side Door Problems?

I'm having some door problems, I'm wondering if this is common with the Grand Prix..I have a 1993 Grand Prix, and all of sudden my key stopped turning in the driver's side door, I had to go through the passenger side to unlock it.

Then a month later the door stopped opening from the outside, then it wouldn't latch, my fiance had to buckle his seatbelt to keep the door closed..it looked really ghetto :)

Finally he fixed it somehow and now it stays shut, but we still have to get in the passenger side to get the driver's door open. I want to get it fixed, but are there any places that work on doors? I wouldn't even know where to begin. And is this a common problem with the 90's Grand Prix?

Any help would be appreciated, thanks!

~Holly