What is the best way to filter out noise on data line?
Trying to send these kinds of signals 30 feet all together on the same cable is nuts.  A much better overall architecture is to send power and simple digital serial signals over the cable.  Handle the details of the stepper control and sensor readings at the far end of the cable, and receive commands and send results digitally.  With the CAT5 cable you described, you can use one pair for transmit, one pair for receive, and the remaining two pairs for power.

Russell has described some things you can do to try and make this mess limp along.  Maybe if you're careful those are good enough.  However, the real problem is in the higher level architecture, which is where any real fix will have to be made.