If you're having trouble deciding what to model, how to get information to help in deciding or to help in planning, how to go about designing and building a layout then you may want to check out "Planning a Layout for Operation". Here is a link to the presentation that I gave at the 2010 Frisco Convention in KC. http://www.frisco.org/shipit/index.php?attachments/planning-an-operating-layout-pdf.10084/ You will find helpful tips, links and hopefully a little inspiration.