There is no sure way to do it, but you can try. Many of the services below are being restricted to protect the provace of the people involved, as well as because of computer crackers... 1) Call the person or the secretary and ask. It is amazing how many people forget about this option. 2) Checking the address if you know the tcp address of the machine. For example, you want to check if mail address name@machine.addr is fine: telnet machine.addr 25 vrfy name quit If vrfy responds with 250 The address in known to the machine Sometime, the machine.addr is not a full address but only an MX record. you can get the full address by saving the following script in hostlook #!/bin/sh # this file is called hostlook MXREC=`nslookup <<_END_ | tail -2 set qt=MX $1 _END_` echo $MXREC with execute permission (e.g., chmod 755 hostlook), and calling it as hostlook ccl.net. Note the period "." at the end of the machine name. It has to be there. 3) Use finger (though it only works with a few machines). E.g.: finger jkl@hawkeye.ccl.net 4) Use gopher. Frequently the organizations provide WHOIS database on gopher which you can search by name. Go to All Gophers, then continent, then country, then organization. If you know, the address of the whois database, you can submit queries directly whois -h osu.edu labanowski If you do not have the whois program, you can still try telned to port 43: telnet osu.edu 43 The list of available whois servers can be retrieved from the anonymous FTP/mail-server rtfm.mit.edu in the directory pub/whois or via gopher sipb.mit.edu You may also find a list of people who recently posted something to the Usenet newsgroups in directory pub/usenet-addresses/lists} of anon. ftp rtfm.mit.edu. 5) There is also X.500 finder on gopher in Europe. You can also do it by telnet hypatia.umdc.umu.se 23 login: de Then follow instructions (one entry per prompt). For example: Simple query mode selected Person's name :- Schultze Department name, * to list depts, to search all depts, ? for help :- Organisation name, :- kiel Country name :- de Germany Got the following matches. Please select one from the list by typing the number corresponding to the entry you want. Germany 1 Fachhochschule Kiel 2 Universitaet Kiel Organisation name, :- 2 Germany Universitaet Kiel No persons match `Schultze'. Displaying organisation details. Germany Universitaet Kiel postalAddress Universitaet Kiel Ohlshausenstr. 40-60 Exit by typing q :- q 6) Use netfind (if you can get to it, it is very busy). archie.au (AARNet, Melbourne, Australia) bruno.cs.colorado.edu (University of Colorado, Boulder) dino.conicit.ve (Nat. Council for Techn. & Scien. Research, Venezuela) ds.internic.net (InterNIC Directory and DB Services, S. Plainfield, NJ) eis.calstate.edu (California State University, Fullerton, CA) hto-e.usc.edu (University of Southern California, Los Angeles) krnic.net (Korea Network Information Center, Taejon, Korea) lincoln.technet.sg (Technet Unit, Singapore) malloco.ing.puc.cl (Catholic University of Chile, Santiago) monolith.cc.ic.ac.uk (Imperial College, London, England) mudhoney.micro.umn.edu (University of Minnesota, Minneapolis) netfind.anu.edu.au (Australian National University, Canberra) netfind.ee.mcgill.ca (McGill University, Montreal, Quebec, Canada) netfind.if.usp.br (University of Sao Paulo, Sao Paulo, Brazil) netfind.oc.com (OpenConnect Systems, Dallas, Texas) netfind.sjsu.edu (San Jose State University, San Jose, California) netfind.vslib.cz (Liberec University of Technology, Czech Republic) nic.uakom.sk (Academy of Sciences, Banska Bystrica, Slovakia) redmont.cis.uab.edu (University of Alabama at Birmingham) telnet bruno.cs.colorado.edu (or redmont.cis.uab.edu or ds.internic.net or mudhoney.micro.umn.edu or hto-e.usc.edu or netfind.sjsu.edu) login: netfind search labanowski osc --- then enter selection and wait for answer. 7) Use NIC WHOIS (mostly military people) telnet nic.ddn.mil whois smith, john quit exit 8) Retrieve files from the directory /pub/chemistry/info/e-mail-addresses a) Via e-mail: send a message: select chemistry size 60kB limit 250kB cd info/e-mail-addresses get college-email.faq.1 college-email.faq.2 college-email.faq.3 get finding.addresses.faq quit to MAILSERV@ccl.net b) Via ftp ftp ftp.ccl.edu Login: anonymous Name: Your email address ftp> cd pub/chemistry/info/e-mail-addresses ftp> mget college-email.faq.* ftp> get finding.addresses.faq ftp> quit c) gopher gopher gopher.ccl.net info e-mail-addresses Jan Labanowski jkl@ccl.net