Cole mentioned a problem I had before but I didnt think of it at first. It could be that your harmonic balancer has slipped on its rubber insulator. The balancer is two pieces held together by a rubber insulator. After time the outer half of the balancer can turn on the insulator.
The easiest way to check for this is to set the car at TDC manually. Then check the mark on the balancer. As I said before it "should" line up with the "T" mark on the timing belt cover.
Since you cant find your timing mark on your balancer it might be a good idea to try another balancer. If I were you I'd take the balancer off and try to find the mark then mark it with whiteout. If it turns out that it doesnt line up with the "T" mark while at TDC then its time for a new balancer.
