Here is a web site for the town of Chomutov.www.chomutov.cz
The information you want, you will need to inquire for in the Czech Republic's archive that handles that town.
Directions to the CR phone book:
in PRIJMENI type a last name, in MESTO/OBEC type a name of the town, take out the checkmark in Diakritika,
click on VYHLEDAT, click on the name to get address and phone number but no zip code there.