For an impressive list of underworld beliefs visit: http:en2.wikipedia.orgwikiUnderworld
The Catholic Encylopaedia contains in-depth discussion about heaven and hell: www.newadvent.orgcathen
Map ofthe underworld in Greek mythology:http:homepage.mac.comcparadaGML
For an insight into Buddhism:http:wri.leaderu.comwri-table2buddhism.html
A good site dealing with comparative religion from a Christian perspective, but with good essays on most of the major religions:www.comparativereligion.com
For a Jewish perspective on the afterlife, go to www.aish.comaishint and search the Ask the Rabbi archive.
An excellent article comparing Christianity with Hinduism can be found at: www.christlife.orgfaitharticlesC_comparinghinduism.html