1: My farmers when set to plant crops do not plant many crops. (Maybe one 3x7 but not much else. and its very slow) i have infact flooded the farm area in river-water and tried to place some potash. Tips?
Use smaller plots or don't use potash. Dwarves will place as much fertiliser as they need before planting anything, and that takes time that could be used for growing. Plots of size 4n-1 are most efficient for potash use, with a three-tile plot requiring only one bar of potash and thus getting planted very quickly.
Once you're ready for planting, dwarves can be rather slow about getting anything in the ground. I've watched a farmer plant one seed, walk to the meeting area and hang about for a bit, and only then get the red '?' and go plant something else. Early on, even if you have a skilled planter, it may be worth setting a couple of spare dwarves to just get the plots filled. But usually, those spare dwarves would be better off gathering plants.
2: One of my dwarfs have made a masterpiece. I cant find it. How do i find it?
Make sure you have a bookkeeper who has an office to work in, and use the nobles screen to set the accuracy to 'high' ('highest' ties up the dwarf too long for my tastes). Give them a little time to get everything counted, and then go to the stocks screen. Navigate to the category of the masterpiece item produced, and press Tab. This will expand the whole list, and then you can look for the individual item.
Alternatively, ignore it. Dwarves can get a bad thought from lost masterpieces, but once they've produced a couple of dozen the loss of one won't bother them. If the masterpiece in question came from a low-skilled dwarf, you might want to put it somewhere it can't be stolen or destroyed. Low-skill dwarves rarely produce masterpieces even with major help from personality and preferences.
3: This game is amazing.
That's a statement. Also, correct.
4: Any efficent way's to find ore/gems/whatnot? (Been mining a giant box for a while)
The site you play on is divided into a number of 48x48 tiles. Digging a 1x1 staircase down the middle of one of these 48x48 areas will hit any large clusters, and has a fair chance of hitting a vein. Gems and other small clusters are scattered around randomly.
5: Did i mention this games amazing?
Yes.
6: What would be a good DF Mode startup? (Generally i go for 2 miners 1 woodcutter 1 Carp/Mason/Building Designer 1 gem cutter/get setter/lyemaker/potashmaker and 2 farmers. If thats a good enough set then just say what you prefer!)
If you're on a friendly site with lots of trees and plants and water and not much danger you can bring seven peasants, an anvil, and a copper bar.
I like to bring a skilled weaponsmith / armoursmith plus a dwarf with some Diagnostician skill, because you can't guarantee those will turn up in a migrant wave. Professions that produce no-quality items are something I leave out of the embark unless I'm bringing lots of raw materials for that product. For example, if I had a civ with access to coal, iron ore, and flux, I'd bring a skilled furnace operator to get all that material processed into steel ASAP. Gem cutting and setting is a luxury profession -- you won't get that many gems naturally, and the infrastructure you need to make a steady supply of raw green glass (or better) will provide the materials for a glassmaker, who can make furniture and trap components as well as craft items.