There are many maps of Europe on line that you can use. You can see an online map of Europe here. If you are traveling, however, a map of Europe in book or CD form may be more appropriate.
Printed road maps and atlases of Europe are very convenient to use. If you are interested in those maps in English, it is best to get them before you come to Europe. Here is a link to a road atlas for Europe and other maps.
When in Europe you will find that there are very many local maps that are most descriptive. And by local we mean both maps of the particular country as well those of a particular city. And it is the city maps that have the most information that is of interest to tourists. So as you travel, look for the local offerings. They may be a little more expensive than something you buy on the internet, but they are really high value in terms of information provided.
If you are going to travel in Europe, you might also consider using a map that can be used with a GPS system. This is one of the most convenient systems to use. Use them in your car or on a train. While you are there, do take a look at the hand held GPS systems. They are particularly useful at those times that you are moving around without a car.
If you came here just looking for a map of europe, here is a simple but effective online map of Europe for you. It is presented by Google and has a lot of detail. Be sure to look at the satellite pictures while you are there. And if you are interested in a particular town, just enter the name and search. You will find a lot of good information.
And here is another. If you click on the picture a new window will open in your browser that will show you a larger version that you can print.