Unfortunatly, you cant trace them.l however, there ARE plugins to stop hackers, such as log in plugins and such. also, be sure your not giving out your .minecraft folder, or the hackers could use your account :/
Thanks for all the ideas! NicoleSaintClaire, i was planing a lido pool, but now im gonna add a water slide! and xXSilentMelodiesXx , i have a dining room and a lido resturant planned, and a bar for the drunks!