There is a great number of excellent web sites in which you can find explanations of the historical reconstructions of the Indo-European languages illustrated with tree diagrams and maps. We present some examples below.

This map presupposes an Armenian homeland of the Indo European people and is taken from The Early History of the Indo-European Languages by Thomas V. Gamkrelidze and V. V. Ivanov (Scientific American, March 1990:110):

Clickable maps and trees can be found in Cathy Ballís Old English Pages the images being produced by Dan Short, Hughes Aircraft, Iceland, and in Cyril Babaevís Linguistic Studies.

A very helpful characterisation of the Germanic language family was published by a team of scholars at the Nederlandistik Wien from which we copied the two tree diagrams below:

A colourful tree of the Indo-European languages is part of the program Exploration of Language developed by Richard Effland, Shereen Lerner, Stephen Parkins and David Turkon:

Materials Unit 1.5: Map of IE Languages