You can find Omegon on any planet by salvaging crashed ships and breaking technologies down into resources. This goes for other valuable resources like Gravitino Balls, Dimension Matrix, Gold, Emeril, etc. as well.
When you break techs down into resources, just go back to your original ship and take it back. (so be sure you have parked it where you can find it again, because after you have accepted the new ship, there is no marker pointing back to your original ship)
For this to work however, you need to be sufficiently far into the game in order for you to find ships with applicable technologies installed. But if you need it to repair a tech on a ship, there is a good chance that crashed ships will have that tech too.