Check your command. It points to the file that is reported as missing.
I would suggest you work through a tutorial before you try to fix the problem by trial and error. One such tutorial is found in the forum FAQ: How to create a bill of materials (BOM)? (already linked above but again for convenience)
If you really want to get your command running then you need to fix the command. Right now it is:
xsltproc -o “/Users/richardrusso/Documents/tutorial1/tutorial1.csv” “/home//kicad/eeschema/plugins/bom2csv.xsl” “/Users/richardrusso/Documents/tutorial1/tutorial1.xml”
The meaning of the single sections is (see: http://xmlsoft.org/XSLT/xsltproc.html):
xsltproc -o [output file] [stylesheet] [input file]
The problem with your command is that the stylesheet file does not exist in the place where you point the command. I would assume that the correct file is found somewhere in the kicad system directory instead of under home. (possibly in the plugins folder)