Common construction supplies are wood, lumber, cement, sand, gravel, nails, etc. For big construction projects, steel is a big component of cost since steel is expensive. The total cost of a project is composed largely of construction materials being used in the project with labor as the next biggest cost component. Efficient materials planning and management can contribute a lot towards lower over-all project cost and helps towards project completion on schedule. Materials management is very essential in large projects to prevent cost overruns or project delays. Nowadays, projects have very tight completion schedules (fast-track projects). Ideally, usage of a computerized system that will integrate procurement, inventory control and delivery is necessary.  A single materials requirements planning system is similar in the manufacturing realms that will reduce avoidable costs such as buying too early, warehousing costs and  pilferages or worse, project delays that cost both time and money. The sites below are particularly helpful and are related to construction materials costing and planning.

http://www.constructionmaterials.com/division.asp?division=01&id=1

http://www.building-cost.net

http://pmbook.ce.cmu.edu