"I am looking for fix-and-forget type (or close to) wind generator of 8 to 15 amps/hour"
Probably no such thing, at least none worth buying. The fix-and-forget type is what I mostly mean. Most everyone around here is building thier own, on this board I mean, so lots of info here how to build them.
Since you don't want much power (for now ) best thing might be the motor conversions. Take any normal AC motor cut the armature flat for 4 equal sides, glue on 4 magnets put it back together and mount a set of blades on the shaft. You'll have an AC output from that so you run the wires down the tower and use bridge rectifiers to convert it to DC and into your controller.
Neo magnets are the best, but most everyone is looking to get higher power all the time, at 12v your looking less than 200 watts. That should be pretty easy to build with some reading here.
Of course there is more you should know and read before doing this, but that sums it up pretty fast and is basically the system. What volts etc.. are other things to figure.
If you can find a decent DC motor like from a tread mill, high volts low RMP, you can pretty much use those as they are with a set of blades.
I have an industrial motor here, 180vdc, 1725rpm, 2hp, 11 amps or more. Plate says 11-6amps actaully. This produces alot of power turning by hand, but it's stiff and I have to check the bearings. Something like this with some blades is perfect, but will probably produce more power than you said you wanted. This one is to heavy also at about 75lbs just for the motor, but for me it should make lots of power and weight won't be a problem.
As for the fix and forget, chances are sometime anything will have a problem and if you build your own then you know how to fix it too. Buy one and need a part you may have problems. Ship back the whole thing to be repaired or wait forever to get a new part?
If you wanted to build a rotor type, take a brake rotor, glue on magnets, wind up some coils of magnet wire, cast in a fiberglass resin with some matting and also have a metal behind the coils to pull the magnet flux through. Or build dual rotor using a brake rotor on eaxch side of the coils. Lots on that on otherpower.com
I buy my magnets from here myself. Wire too.
You can make your own blades various ways, some pretty easy, or Jerry sells some good blades pretty reasonable.
As for cost, it is certain that anything you build will cost less than buying something already made, and most likely work far better too. Proably only real exceptions would be buying an older large unit or buying a homebuilt from someone around here if they were selling one.