The great news about shohin and mame is that you can get away with the absolute minimum in tools.

I good pair of shears is your starting point. Something along these lines: http://www.thebonsaistore.co.uk/inc/sdetail/283
Next would be the small size (170mm) Concave branch cutters: http://www.thebonsaistore.co.uk/inc/sdetail/2892

Regarding books - the Morten Albek one. Here's his website: http://www.shohin-europe.com/

The techniques for shohin/mame are clearly similar in many ways (propagation, general care) and differ in others (pruning, watering requirements, soil composition).

Read these articles: http://www.shohin-europe.com/articles.html

Although they're easier to lift, that's about all that's easier about them compared to larger bonsai.

Shohin and especially mame, are more difficult to design, maintain and care for than larger bonsai.

It's all because smaller is less forgiving than larger. The smaller the tree, the less room there is for error.

Practically, they are alot more trouble than larger trees. With shohin and mame, soil volume is vastly smaller than in larger bonsai. Shohin and mame dry out very quickly (and a balcony placement would expose them to windier -and resultingly drier conditions). They're also more vulnerable to temperature (they can heat up very quickly and dangerously in the summer if left in sun). Both temperature and especially drying out can lead to almost instant death in a single afternoon. Drying out is a particular issue with smaller plants. Many mame and shohin enthusiasts make special tables that hold several inches of sand and push their trees into it --watering the sand--to maintain a more even moist environment. They're also chained to a more rigorous watering schedule than bonsaiists with larger trees.

Artistically, small trees are more technically demanding. Since there is less room for branching and leaves, each branch and leaf increases in significance. One leaf can sometimes stand in for an entire branch on a mame tree. If you're too aggressive with pruning, inattentive to watering for a single afternoon, and you lose a branch, your entire design of the tree is pretty much ruined.

Well designed and maintained mame and shohin are not an easy thing to pull off. Good shohin and mame trees are the mark of an experienced bonsaiist.

These seem fine.

Not to harp on this, but unfortunately, your artistic capabilities are at the mercy of your horticultural skills. That's just the way it is in bonsai. If you can't keep a tree thriving (not just alive), design choices will be extremely limited, or non-existent if the plant passes away. You already seemed to have had a bad experience with larger trees. Smaller trees are more difficult in every aspect.

It's great that you will be around to care for your trees. That increases your chances of success.

Regarding tools, you're preparing to throw a lot of money at a problem that mostly doesn't exist. You don't yet have (from what's written here) trees. You're putting the cart before the horse. Additionally, concave cutters for small trees may even be a problem if their cutting edge isn't proportional to the tree you're working on.

The regular cutters produces different scars than the round cutters (necessarily).  Some trees heal better w/ a different kind of cut.