Looking for a way to be notified when a domain becomes available

Hi, I'm looking for software or a way to determine the moment a domain becomes available.

I'm researching domains, and found a few which we're due to expire over the last few days however by the time I try to register the domain they have been registered already.

Is there a way to know the exact time a domain becomes available rather than just the day.
Also are their any tools which can email or something when a domain is available to register?

Thanks for any help

You can use domain monitor @ DomainTools.com
They will email you whenever your listed domain name whois change.

For free alternative, you can also use domain name drop date calculator at domainrecover.net
Just enter the domain name expired date, then they will calculate the drop date, you can register it right after it drop.
If it is a good name, then you will compete with many companies.