OK - some basic stuff about my 1 foot square terrain tiles.
My intent isn't for landscaped squares, but rather a changeable system of pieces. Instead of sculpted hills, my hills are contoured sections that create hill edges, that can be wrapped back around themselves to create hills, left "open" to creat long ridgelines, penetrating hill edges onto the table, etc.
The basis for all the terrain squares are 1 foot square vinyl tile, 1/8" thick. Mine are made by Armstrong, and cost around $.70 to $.80 per tile. Tile is a wonderful choice for terrain that lays flat. It doesn't warp when you paint or finish it, and it doesn't dimple or get damaged when players lean on it or place their hands on it during a game. We've played about a years worth of games on my terrain, and the squares look just as good as new.
I double up the squares, so each 1 square foot section consists of 2 tiles, glued back to back to each other. These are the basic squares, that form the basis for the baseboard terrain. To glue the tiles together, I needed glue that was a consistent thickness and consistency so that the terrain pieces were of equal thickness. I use thick, gap filling cyanoacrylate clue ("super glue") to glue the pieces together. I apply a nice bead of glue around the perimeter of the bottom piece, and "swirl" so glue around the middle to make sure there is even distribution of glue to hold the tiles together. Place the top tile on the bottom and make sure the opposite corners line up - just use your thumb and forefinger and "pinch" at each corner. Your sense of touch is more than accurate enough to get the pieces lined up.
I'll post later about making rivers and roads and hill sections. Its all about the same, but there are some tricks.
As for a rock hard durable finish - its pretty simple. I use a cheapo gallon of latex interior wall paint that I bought at Home Depot. Pick the color you want for your base - be aware that the tone and some of the color will be visible. Mine is kind of a pumpkin/brown color.
I use a 4" wide paint roller, and just roll the paint onto the top of the 2 tile terrain section like I'm painting a wall. Make sure its totally and evenly covered, and wipe off any excess that slops over the edge.
While the paint is still wet, apply the covering flock. I use a variety of Woodland Scenics colors - green, turf, blended turf, yellow grass, earth, etc. I have a large plastic storage box that I use to put the flock into my high tech flock dispenser utility device (HTFDUD). Normal people would recognize it as a squeeze flour sifter, but to a wargamer its the perfect means of evenly applying flock to freshly painted terrain. To a wargamer, its a HTFDUD.
Anyway, pour the flock color, or colors into the sifter. Sift the flock over the tile where you want that color. You can get a natural variation in the grass color on the tile by first applying a shade in some areas on the tile, then putting a different shade over more areas, blending them together with different shades. Its much easier than it sounds.
Let the tiles that are now flocked set over night so the paint dries. Next day, tip the tiles on their side and blow off the extra loose flock.
Now its time to apply the HTWSSaDC (High Tech Wargame Surface Sealer and Durability Coating). I buy mine at Home Depot (aka Wargamers Depot). Don't look for HTWSSaDC, but rather you want to buy a gallon of Minwax water based Polycrylic - a clear protective finish. I use clear satin.
Again, you'll apply this clear finish using a 4" roller. (I hope I don't need to tell you that you need a paint pan to put the paint into to use the roller....). Go for an even, but fairly thick coat of the clear finish. It will darken and mute the flock colors, and tie the whole mess together. Let sit over night, and ZOWIE, you have virtually indestructable terrain squares. If you ever do have damage, just hit them with some clear, add flock, and then clear again once that flock has dried.
Some random photos of the terrain: