Super,
If you want to keep the wiring to a minimum why don't you just use the strips of surface mounted LED's - you know similar to the ones you get in those 'Lego LED' sets we been buying. You can get those LED's in the form of a long strip on a reel, these are marked so you can cut them to the length you require (typically they are marked to cut every 3 LED's).
Then all you need is the two fly wires to the solder pads on the end of the strip you have cut off. As to how many you can power from a 9v battery, that is something you'd have to play around with
If you want to keep the wiring to a minimum why don't you just use the strips of surface mounted LED's - you know similar to the ones you get in those 'Lego LED' sets we been buying. You can get those LED's in the form of a long strip on a reel, these are marked so you can cut them to the length you require (typically they are marked to cut every 3 LED's).
Then all you need is the two fly wires to the solder pads on the end of the strip you have cut off. As to how many you can power from a 9v battery, that is something you'd have to play around with
Happily collecting things all my life... 
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