Updated: 2011-12-28
The .minecraft/redpower/redpower.cfg file contains the block ids for ores (inc. gemstone ores) and stones (marble/etc).
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blocks {
    array.array.id=252
    base {
        appliance.id=137
        microblock.id=136
    }
lighting {
        lampOff.id=147
        lampOn.id=146
    }
logic.logic.id=138
    machine {
        frame.id=152
        machine.id=251
        machinePanel.id=238
    }
sensor.sensor.id=148
    world {
        crops.id=144
        leaves.id=141
        log.id=143
        ores.id=140
        plants.id=139
        stone.id=142
        storage.id=145
    }
}
The .minecraft/config/IC2.cfg file contains a line 'valuableOres=' and a list. The list has a format of blockid:value,(space)
The normal minecraft blocks are obvious; the industrial craft blocks IDs are defined in this very same file. All that's missing is telling IndustrialCraft which /other/ blocks to mine for. In my case 140:2, 142:2, was missing.
Hayo! The automated miner does a nice job.
( BTW, if you want it to also get more cobblestone, sandstone, clay, etc, just add the block IDs to that list. This should also work for glowstone and other resources... but I'm not sure if it is able to collect material before it drops/if it is surrounded by lava O.o )
Here is my current line (this will even 'mine' RP2 trees, but that's REALLY costly compared to breaking out a chainsaw!):
   valuableOres=14:3, 15:4, 16:1, 21:3, 56:5, 73:3, 144:1, 141:1, 143:1, 140:2, 139:1, 142:1, 247:4, 248:2, 249:2
 
		 
		
		
	


