sway bar links can be tough to diagnose...if its a hollow sounding noise...i would think about them though even though they feel tight....
based on what you have told us, first look at the tips of your front leaf springs to make sure the plastic insilators that are between the two leafs arent missing or broken...then i would replace the shocks...they need to be done if they are seeping anyway....if that doesnt fix the noise, then i would put a coupld sway bar links in it...