Google Adwords Expert

I own a membership organisation and need someone who can help me with my google adwords campaign, It is very successful as far as it is always No1 in the listings, but I think it is costing me much more than it should do because of my lack of experience in this field for example I don't understand 'display networks' . I need someone to look through what I have at present (key words etc) and make my campaign run efficiently and effectively without paying more than I need to.