I've been using www.dnsstuff.com and samspade to check out where my visitors are from.

Are there any other sites that have more detailed info such as a specific location or identifier if the user is using their PC at home or other computer?

I generally check the IP address in whois or information. Then I check the dns lookup (usually using the "all" selection and sometime get a website url, but most of the time get an ISP like comcast or cox or rr along with a city. Is the city usually accurate from this search. Also is there a database of the code of dns for ISPs like AOL and such that you can figure out where the IP range is geographically located?

Just trying to figure out more info on who visits my site.
Thanks

You could check RIPE [ http://ripe.net/ ] db lookup.
Ripe is handling European allocation of IP blocks to enterprises.

You can find links to the other organisation doing the same for Africa [ http://www.afrinic.net/cgi-bin/whois ], Asia [ http://wq.apnic.net/apnic-bin/whois.pl ], USA [ http://www.arin.net/whois/ ] and Latin America and caribbean [ http://www.lacnic.net/cgi-bin/lacnic/whois ]

such as a specific location or identifier if the user is using their PC at home or other computer?

You might find more details in your site's log files, have you looked at those ?