Disneyland does not do anything special for Easter (they used to have an Easter buffet but not sure that's still going???).
You can find a couple pins & stuffed animals in easter theme & some goodies at the candy shoppes....other than that they don't celebrate it in the parks.
If you are looking for religious services during that time, the Crystal Catherdal is very close. And I think they have a Mass available at the DL hotel?