Edward, you can get the information from applications like Norton Internet Security.
This is the latest one I got
inetnum: 83.27.128.0 - 83.27.255.255
netname: NEOSTRADA-ADSL
descr: Neostrada Plus
descr: Poznan
country: PL
remarks: ! - ! - ! - ! - ! - !
remarks: Contact to ABUSE TP S.A. :
remarks: abuse@tpnet.pl
remarks: ! - ! - ! - ! - ! - !
admin-c: TPHT
tech-c: HT2189-RIPE
status: ASSIGNED PA
mnt-by: TPNET
changed: hostmaster@tpnet.pl 20031211
source: RIPE
% RIPE database, last updated Sep 21, 2004 12:10:28 AM
So my question is, now that I have this information, What can I do to stop this person from attempting to connect to my machine?