Here is some handy information on your steel and bolts;
Weight calculator;
http://www.portlandbolt.com/steel-plate-weight.html
Weight chart;
http://www.engineeringtoolbox.com/st...ht-d_1561.html
Bolt Grades;
http://www.engineeringtoolbox.com/st...es-d_1426.html
http://www.engineeringtoolbox.com/st...es-d_1427.html
http://www.engineeringtoolbox.com/st...es-d_1428.html