You can find many artifacts from the ancient and medieval period by paying a "virtual visit" to the world's greatest museums!
The list below contains both primary and secondary sources related to Western Civilization.
Ancient History Encyclopedia
An Encyclopedia of general history resource, covering all time periods of human history.
The Avalon Project
Primary documents in law, history & diplomacy from Yale.
British History 1700-1920
An edited collection of materials from Spartacus Educational (UK).
Diotima: Materials for the Study of Women and Gender in the Ancient World
This site contains links to many online resources, including articles, book reviews, databases, and images. The Anthology tab has a wide variety of translated materials with an "anthology of translated primary sources," which includes Greek, Latin, and Egyptian texts.
Library of Congress - World History & Cultures
World History and Cultures collections from the Library of Congress
Livius
Offers information on Ancient History.
Luminarium: Encyclopedia Project
The Who and What in Medieval and Renaissance England.
Here are a few website recommendations to get you started as you search for images.
Smithsonian Images
The Smithsonian Museum has thousands of images from their museums which students and teachers can use free of charge
World Digital Library
This contains all kinds resources from around the world! You can search by place, time, and topic. All materials appear in their original languages, but descriptive text can be translated into 7 languages, including English.
Library of Congress
There are a number of resources here, from historic newspapers and maps to images and video.
BBC: HistoryExtra
The BBC has done a great job bringing together historical topics, timelines, and images.