NOTE: this is capable of killing most things except big game, so DO NOT attempt to shoot anyone or anything without thinking of killing it, and if you do, I am most definatley not responsible for the death or injury so be-friggan-ware.
Also note that the crossbow should be made over a span of 2 days, the second day can be spent assessing the crossbow, tweaking it and adding features.
Step 1: Materials
-Ratchet saw (that motorized hand saw thing)
Note: if you do not have this you will be sore from cutting the wood out with your hands, so yeah, this tool helps.
-Coping saw (any saw will do)
-Vice (absolutely, positively needed)
-Carving tool (last picture), fairly useful, if you can get one.
Note: I have gone into detail, just in case some idiot complains about it.
Deadly Resources required:
-Wood (1 metre length and 15 cm width, which is about 3 feet length and 6" width, I think).
-String (strong, the thicker the better)
Note: Wooden blinds can be substituted for bamboo, I will go into more detail in step 3.
Step 2: Marking and chopping wood.
Chop the wood with the Ratchet, make sure that the wood is in the vice or you will be missing a few fingers after this step.
The chunk taken out of the body should be kept unless you have scrap wood lying around.
The chunk of wood that has been chopped off you should now put into your vice look at picture 6 to see where the screws go, drill them in slightly so the're in there but not completely through the wood, now remove it from the vice and clamp the base there, then fully screw in the chunk as shown in picture 5. This is the stock.