I would like to know if I need to get my H1b amended?

I filed for my H1b in 2012 and it was approved . At that time I was working for New York City - Taxi Limousine Commission and in January I started working for New York City - Landmarks Preservation Commission . I am planning to go for H1b interview and I will get the client letter from New York City - Landmarks Preservation Commission . . So in my case am I supposed to get my H1b amended or just need to update the LCA with the new client location ?

Even if you are with the same employer and in the same city and even if you have a new LCA, since the end client has changed you should get the H1 amendment done. Although I have seen cases where the H1 was not amended and only the new LCA was filed and they still got their H1 stamped but the correct way should be get a new LCA and the H1 amendment.

Look here

I completely second Ankit1912.

Please make sure your Petitioner gets it amended and you have your new I797 before you appear for the H1B interview.

Good Luck!