Network domain lookup and diagnostic tools:-

..:   Domain suffixes    

..:   Dig it man!    Get DNS data on a domain.
..:   IP locator    Find the location of an IP address
..:   Another IP locator

..:   Whois lookup, Africa
..:   Whois lookup, Asia and Pacific
..:   Whois lookup, Northern America
..:   Whois lookup, Southern America
..:   Whois lookup, Europe

..:   NetNames - Domain Management Services

..:   Check multiple DNSBL listings.
..:   Another DNSBL database check

..:   Nominet    Domain registry for all .uk

..:   Netcraft What's That Site Running Results   Check server configuration and uptimes.

..:   Domainmonger    A quality domain registration service.

..:   DSL speed test    (requires java)