Pontiac Repair: Windshield wiper linkage?, windshield wiper, thunk

Question
Hello, I have a 1998 Grand Prix GT.  I turned the wipers on yesterday morning when I hadn't realized they were frozen.  The driver's side came unstuck and worked properly, but the passenger's side stayed stuck.  I got the wiper unstuck myself, and found that the arm moves relatively easily when I move it.

When I turn the wipers on now, that wiper may move part of the way or not at all.  When the wiper lowers to the cowl, I hear a "thunk".  

Is it likely that the linkage is broken, or could it be something else?  Is it something relatively easy to fix?  On a scale of 1-10 on do-it-yourself auto repair, I'm probably a 3-4.  If this is something best left to a mechanic, how costly is the repair?

Thanks so much!

Answer
Hey Jeff:

I think #1 the arm stripped off the transmission stud on the passenger side and the transmission is also bent causing the noise. It's not to hard a repair. as for the cost maybe $200.00 for parts. The arm may be a dealer only part you may be able to find the transmission aftermarket which will save you some $$. good luck :}