I use chunks from a big box store in my smoker. I normally use 3-6 oz of apple or cherry for most smokes for pork and turkey. For beef I may use some hickory. For fish I use alder. Cheese gets 1/2 cherry and 1/2 apple for 2.5 hours.
Suggest you weigh your wood for the first few smokes, too much can make a bitter taste. Watch your wood for signs of combustion (no charcoal, only ash) when you season it, that way when you go to smoke you can put the wood where it won't combust and make bitter smoke.