I am a little late as usual but I wanted to share my thoughts. Beings you are fairly new to this, you are probably going to want to make changes as you build. I recommend avoiding the postcrete & quickcrete as it gets hard like concrete. Here in the eastern US, we use either #10 crusher fines (very small stone w/ stone dust mixed in. Very cheap as it's basically a byproduct of crushed stone and can be obtained at most limestone quarry's for next to nothing. It may be available at some brickyards too. Some people even use chicken grit. It looks like very small stone maybe a little finer than #10's. When I did mine, I dug a trench down just below the grass root line or maybe a little deeper. I then laid some landscaping cloth (black plastic trash bags cut into strips work too) on top the dirt to keep the weeds and grass from later popping thru and then filled the rest with the stone. Work the track back and fourth or side to side to sink it into the ballast some. I used LGB track and clipped it together with the LGB plastic tie clips. No special rail clamps, just factory brass rail joiners. Most important, put some kind of Dielectric grease in the rail joiners before you slide your track together. I used the LGB rail joint anti-corrosive paste. It will last for many, many years. Our climate her is 90+ Degrees in summer and we get our fair share of rain too. In the winter, low 20's at night and sometimes single digits near zero. Some snow and a lot of freeze then thaw. My track has been down 15 years with no loss of current at the joints. Just clean it few times a year with 3M green colored scotchbrite scuff pads. Hope this helps.