Many of you will know this already, but for the new players joining it might prove useful..
It's very easy to forget particular systems/places of interest over a period of time (especially if your memory is like mine and still running on 640K). As the current incarnation of the Galaxy Map does not allow you to set "user defined" markers (I remember centuries ago that Google Maps allowed you do do this ), you can buy a cheap stock sidewinder and leave it at the location. This will allow you to quickly home in on a system. It's also pretty useful to set a location if you are doing timed trade runs too.
Hope this helps!