I just had the computer replaced on my Toyota Camry and it was running again, but now it has trouble starting. It will rev and rev but not turn over and start.

I would suspect a fuel pump issue. The filter won't change it's performance if you squeeze a line. I would test the fuel pressure regulator and the fuel pump. See if you can hear the fuel pump hum when someone turns the key to the ACC. position. You should hear the fuel pump hum. You may also have a bad coil connection. Check for good spark also.