I have got to the stage where I have had Wuubfurth put in prison. I will go back today but can I still sell the amulet to calixto. I originally never talked to him because his house was locked so I went to the woman viarmo whatishername. I really don't want it, I can tolerate books and misc items but in my apparel is just horrible.

If you don't sell it to Calixto when he offers to buy it, you will be stuck with it forever (unless you are on PC and can use console magic or mods to get rid of it).

Damn it, I could never sell it because his house was locked and never opened.