Command Line
 

Just downloaded Maya 8.5 Learning Edition Trial version,
I want to install a plug in to export a maya file to an OBJ export format, on the readme file it states to load the plugin into maya,
then type write Arp in the Maya Command area and hit return,
where is the command line.

thanks

Its the grey line at the bottom right of the screen.

Press F1 for the help files and then go to search that will tell you pretty much everythinng you want to know, although i'm not too sure if the PLE will let you export as an obj due to its restrictions.