Dating-style website needs back-end work

My site is run on a dating script I purchased. I need help with the following edits: 1) I edited the HTML on the member registration page to create new form fields. I need to have the corresponding PHP and SQL database changed as well so that the new information can be stored and retrieved. I also need to have form validation. There are a few fields I wasn't able to change. I need to have Area and Nearest City changed to a zip code field that will automatically populate the member's City and State. I would then like to be able to search by miles from zip code. 2) The search box needs to work correctly with these new fields. 3) The Edit Profile page needs to work with the new fields. 4) I need the site tested for bugs/made sure it's working as it should. I would also be interested in having you offer any suggestions you may have to improve the site and we could talk about how much it would cost to implement. Once I get this back-end code working correctly, I am going to have a front-end person/designer go over it and make it look nicer. If you could help me with this too cool, if not it's fine. If this sounds like something you can help me with, I will send you the site URL so that you can provide me with an accurate quote and time frame.