thanks energiser
edit: okay i've built espionage probes but i can't send them anywhere 
OK, now just go to the "Galaxy" page, in the right hand column of the table (marked "Actions") there should be 3 or 4 buttons on each line, where each line corresponds to a planet. The left-hand most of these buttons should look like a notepad page, with an eye in the center. Click this and it will send your probes at this planet.
NOTE: You spend 10 deuterium for each galaxy page you view, if you don't have 10 deuterium, you can't view the page. Also, you need deuterium to send ships anywhere, espionage probes don't need much, but they do need some. The amount of deuterium needed to travel somewhere does increase with the distance that the ship has to travel to get there, as does the travel time.
