The engine's not going to start without the ECU. That's what controls the amount of fuel going into it (among other things), and with no ECU you have no fuel. No fuel, no start.

If you want to get a new one for cheap, search for "obd2 p75" on ebay. This is an example of what you should look for.

Keep in mind that you will need to make sure it's out of a car from model years '00 or '01. If you buy a '96-'99 ECU the plug will be slightly different from your car's wiring harness.

One other issue I'm thinking of is the immobilizer function of the ECU. I believe there is a chip in your key which "talks" to the ECU and if the key and ECU don't match then the car won't start. I would check with a dealer to see if they have the capability to match up an ECU with the key or vice versa.