Re: sewing/dyeing with interlock
google dyeing fleece/yarn with kool-aid, food coloring, wilton's icing dyeing. You'll find a millon sites/tuts on doing it. Also look up acid dyeing in wool.
It's really simple.
Can be done in a crock pot easily. Basically, soak your wool item in water for 30 min. Take a crock pot (don't use it for food afterwards so a trip to the salvation army for a used one is in order). Fill about 2/3 full of water, add a generous pour of white vinegar (a good glug or two), add the dye (kool-aid/wiltons/food coloring), and submerge the item to be dyed.
Turn the crock pot on and leave it alone for about 30 min. DO NOT DUNK SWIRL STIR OR OTHERWISE MOVE THE ITEM or FELTING/SHRINKING/BAD STUFF will occur.
Check after about 30 min, if the dye bath is clear then all the dye has been absorbed and voila you're done.
I leave the item to cool in the dye bath before taking it out to rinse.
This can also be done in the microwave, on a stove top or I think even in a dishwasher.
Commercial acid dyes work in the same manner and will give more intense/greater variety of colors.