Arrest Needle is obtainable by combining PROOF OF SONIC TEAM (aka POST) with a Spread Needle (found year around, you can check drop table for what drops them and where). As for the Easter event itself there is no specific quest for event/items, it just depends on what item you want to hunt and do a quest with the most of the enemy that drops that item or whats most fun for you. Often time drops do not change much between the years so you can check forums posts for confirmed drops of last year (or wait for an updated one a player is willing to make this year when event starts), for an idea of what and where to find items my I point you to this post from last year