A long time ago I watched this movie about a group of high-tech werewolf hunters enter a very old town and one of the hunters is a vampire. The vampire falls in love with a humans girlfriend who wants to become a werewolf hunter too. PLEASE HELP!!

Your description is so close, had to throw this one out there:
Underworld (2003) - IMDb (http://www.imdb.com/title/tt0320691/)