Web pages on the civilizations of South America feature a wealth of photographs and information, such as the Andes Web Ring, hosted by James Q. Jacobs: http://www.jqjacobs.net/andes/
For tourist guides, interactive maps, and great photographs of Machu Picchu, check out the following: http://www.peru-machu-picchu.com/; https://whc.unesco.org/en/list/274; http://www.raingod.com/angus/Gallery/Photos/SouthAmerica/Peru/IncaTrail.html.
See also UNESCO World Heritage Centre’s page on the Spiritual and Political Centre of the Tiwanaku Culture: https://whc.unesco.org/en/list/567; the Chan Chan Archaeological Zone: https://whc.unesco.org/en/list/366; and the Lines and Geoglyphs of Nasca and Palpa: https://whc.unesco.org/en/list/700
Ancient History Encyclopedia’s pages again provide nice summaries, with photographs and videos, such as Moche Civilization: https://www.ancient.eu/Moche_Civilization/; Tiwanaku: https://www.ancient.eu/Tiwanaku/; and the Nazca lines: https://www.ancient.eu/article/665/nazca-lines/
On the topic of Inka child sacrifice, see Kim MacQuarrie’s webpage at http://lastdaysoftheincas.com/wordpress/inca-girl-frozen-for-500-years-now-on-display#.UPLZ56VgP8s.