There are some very good threads here if you do a search. Many women find taking certain supplements from mid-cycle to the beginning of their period helps a great deal.
I have awful PMS. I get so moody and almost paranoid (I think no one likes me...but their may be a good reason for that...lol). The last couple months I have started taking evening primrose oil and I have seen a difference. I also up my water and protein intake. Sometimes just realizing that it's hormones helps me feel a little more normal.