Skymaps is a really useful site that simply provides a free downloadable monthly sky map each month. The maps are of the type found in the centre of most monthly astronomy magazine, and can be printed quite clearly on a standard inkjet or laserjet printer. The main drawback of the maps is that they are prepared for North America, and therefore are for a latitude of around 40 degrees north. We are considerably further north at around 53 degrees, therefore objects shown near the southern horizon on the map will be below our horizon.
That said, the advantage of these maps is the second page which includes a list of objects visible during the month. The list is nicely categorized into naked eye objects, binocular objects and those visible in a small telescope. This is really useful for planning you observing and choosing objects suitable for your level of experience. Major astronomical events during the month. All in all a very neat package on two sides of A4, and one we often use at our CAS meetings.
In addition to the free downloadable maps (you can get a southern hemisphere one if you are heading south on your holidays), you can also purchase commercial sky maps, atlas and planispheres etc.