Small details

I recently was recommended to take a look at 'Unit Models'. This small family business makes great details and items that are ideal to further detail structures or add items on other areas of your layout.
There's small US style mailboxes, roof vents, oil drums, small sheds , relay cabinets etc etc.

Their range certainly contained some items that I really liked, so I placed an order for some of these, and will use them (among others) for my warehouse.
Take a look at http://www.unitmodels.com/  . I've now added them to my ever growing list of useful links.

Creating a believable railroad

There are many factors that help in creating a realistic model railroad.  All too often, we focus on painstaking detail, weathering , scenery etc etc. However, another crucial element is to have a good look and do some research when you're buying your locomotives and rolling stock. If your goal is to have great realism, and you're modeling a branch line, then a Big Boy, or a consist of SD70Ace locomotives isn't going to look right.  Similarly, you have to avoid a collection of 'exceptions'.
With that I mean, that while a certain type of loco , or guest railroad (lease power) showed up at some point, having that on the layout might not come across as realistic. Instead go for the ones that would be there most of the time, perhaps this was in the shape of GP38-2 locos, and of a certain road.

The same goes for your freight car fleet, make sure you have sufficient of the 'home railroad' , that you would commonly see to make a convincing scene. There are many boxcars I'd like to have, but I have resisted buying them because they would not have been around or seldom in the area and era I model. I came across a set of 5 Cotton Belt box cars recently, all with different roadnumbers.
Now those I can use, as my layout is SP/CFNR, and Cotton Belt box cars were quite common place in California. I need to do a lot of weathering and some graffiti attacks to these, but they do convey the fact that my layout is SP territory predominantly. 
Here they are shortly after arrival in the mail, on my module. They will find good service on my home layout in time.

progress on the warehouse

It's been a little while since I've been able to continue on this project, but here's the next stage (the warehouse is not placed in the right spot here btw)

I've applied a 'concrete' foundation by finding a suitable concrete pattern on the internet, scaled it down into strips and printed it out on a colour laser printer at work, and glued these to the structure base using PVA glue. Next I used a black craft paint (same stuff they use at pre-school etc) to paint the roof, and sprinkled on Woodlandscenics B76 cinders ballast while it was still wet. It will be followed by a layer of diluted PVA glue to further fix it in place. After that it is time for detailing the roof etc, but I first need the detail parts (such as AC units, vents etc) which I haven't even ordered yet....