Oh i got a longer ruler than 24 inches. it's at least 36 with a lip on it. cant' remember who is was by. it's lines are in black.
the main rulers i use are Omnigrid and Omnigrip (those just have a bit more stability stuff on the back). good luck.
I just saw some online 4x36 inches called O'lipfa craft ruler. you might try to find those.