Right, it's here and it's gorgeous. a 07 cromo absolut

I'm going for 24" wheel single speed build. Already got a nice DMR rear wheel and a 16t freewheel. Probably going for Dirt jumpers, but have my eye on some cheap dirt jam pros just to get me started
Does anyone know where I might lay my hands on some information about BB sizes and seat tube diameter?
Any suggestions about cranksets, bars and stems? I'm new to all this dirt jumping malarky.