Hello,
You may try whois.sc for checking a domain's WHOIS information. This site provides pretty good information and has good design.
To continuously monitor a host's uptime, I discovered a site named ServiceUptime.com
The periodically monitor a web site and alert you via email when a specific service on a domain is down. Mostly people monitor the http service which run on port 80. You may visit that site to check for a specific web host's uptime statistics as well. Pretty helpful if you are unsure about a web host's uptime guarantee.