Welcome to the Forum
For beginners I use this site. More can be found on the web. http://www.thortrains.net/
Track plans are normally limited to table size, track pieces and switches!:laugh:
Track laying I use the plywood, no roadbed.
Cork would be my preferred choice, although it can get expensive...
As for layout plans, you will want to see what's out there for some design inspiration, before I was able to design my own layouts I spent ALOT of time studying track plan books and plans I found on the internet. Before long I was doing stuff like this:
Basement G scale layout (older plan but you get the idea)
HO Scale Marklin Layout if I had the proper space and $$$. This is my multi-level masterpiece