Can I load program a micro with a .out file like I can with an ELF or HEX?
Yes.  The .out file is actually and ELF file.  Set the debugger in your IAR project options to be J-Link/J-Trace.  In the download tab, check "Verify download" and "Use flash loader(s)".  When you debug the project, the microcontroller is programmed as part of the debugging process.

If you would like, you can also choose the "Output Converter" category on the project options dialog and generate an output file in addition to the .out file.  You probably have choices of Motorola S-record, Intel-Hex, or straight binary.