What would be your workflow?

Question

Hello,
This is my first post, and I am a new photoshop user (CS2 ), so please be patient with my "noobness. "
I am reasonably computer savvy (program in several languages) and have done graphics work sparsely in the context of developing a video game, but I am not very experienced with photoshop per se (my work has been a combination of gimp, trial photoshops, etc.) Most of what I accomplish has been through combining textures generated by my game engine with high level shader language.
I have a project now that I need to do in the next two weeks which is "simply" to create a booklet cover- it may be beyond my capability, but it looks relatively simple and I am seeking general advice, and specific direction on a couple of issues.
I need to make a graphic after the style of the attached .jpg.
It looks to me relatively simple- but not being that familiar with making things like this I really do not know. I have perhaps bitten off more than I can chew in the next two weeks given that I will be learning as I go.
The way I would proceed would be to create several layers for each element (e.g., bushs, beach, ocean, mountains, buildings) and then go about drawing items. (I am using a Wacom Bamboo pen & touch- which I am also learning on the fly)
My more specific questions have to do with
1) gradients
2) spackling (for lack of knowing the correct term)
3) texture
1) How can gradients be achieved? I have used the gradient tool in the past to fill a selection with a gradient between two colors, but is there a way to create gradients that flow between two colors as you draw with a brush?
Consider the areas circled in red, especially around the blue mountains. That is where I am assuming some gradient function might be used, but if there is some other function by which to obtain that type of fading between colors I am completely open to suggestions.
2) in the circled bush, as the green fades into the darker brown, there is what I would call "spackling" or discrete points of the brown on the green (as opposed to what might be obtained with a smudge tool). How would one obtain that effect most efficiently? is that just a matter of playing with brush scatter settings and so forth?
3) As the original is an artwork created on a physical canvas with physical brushes, it has a texture. How are such textures accomplished with photoshop?
I realize that my questions may be relatively "big" but what I am looking for is starting points.
If someone would take a look at the attached picture and think about how you would do it yourself, I would appreciate a general description of your workflow and a listing of any techniques/tools/settings that I should investigate further.
All the best,
Byron

Answer 1

Hello!
Here a few "starting points" for the some of the questions that you have above.
How to achieve a gradient background:
You will want to create the gradient and place it on a background layer. For the mountains, you can create a custom shape and apply a gradient. 
Create texture:
You will want to use blend modes and textures for the mountain and possibly other areas.
Hope this helps give you a starting point with your project, and please post back as you proceed with your project.
Janelle