Congratulations on making the decision to Build.
What you will want to do first of all is have a floor plan in mind of what you want to build. Then research builders in your area that build that type of house. For example-have you seen any new construction models of the style you have in mind-One Story, 2 Story, Modified etc.? If so check out these builders. I recommend checking with 3 builders who build the style of house you are looking to build.
The price per square foot comes down to many overall components such as: finished square feet, style of the home, the upgrades used, flooring, woodwork/trim, infloor heating etc. I would suggest checking with your local builders association to research the builders in your area.
In Minnesota we have the Builders Association of the Twin Cities. The website is: http://www.batc.org where consumers like yourself can research builders and remodelers by price range and area. I also recommend hiring an Realtor who specializes in new construction sales to guide you through the process. I myself am a CSP-Certified New Home Sales Professional specializing in new construction. Your agent can help you with: Lot Selection, Financing, Specifications, Blueprint Reading, Allowances and Extras, Legal Documents, Builder Selection, Upgrades/Options, Walk Thrus and Designing for Resale, Home Inspections and the Warranty of your new home.
Keep in mind not all agents specialize in new construction, so be sure to research and ask. A good agent will save you time and money and will look out for your best interest. And it is also important to note that the realtors commission is paid by the builder and is already figured into the sales price.
Lastly, it is also important to note that builders are craftsmen and women and specialize in offering different floorplans, styles and finishes. What one builder offers as an "upgrade" may be another builders standard in pricing.