I have a 208 Volt 3 phase heater that I would like to use in my garage. My garage is wired single phase I have (2) 220 volt oullets wired one 30 Amp and one 50 amp plug's. Any way to convert this heater or buy a device to interface as to where I could use it?

3 phase converters are available. Installation is not simple and they are very expensive. That's why a lot of used 3 phase equipment seems inexpensive. You can run 3 phase to your house. Your utility will charge you for all of the extra wiring and trouble if it is not available at your pole ($$$$$$$). Sorry, get a different heater.

You cannot simply run 3-phase to your home. The vast majority of residential areas do not even have it available at the road and utilities are not willing to bring it in for one customer.

Id definitely agree, if it is available it's not worth the cost. Not unless you are going to have a professional shop going or something.