i have a 2jz motor that has a knock in it i need info on what the problem could be.
where can i find parts to fix it?

Well in realistic sense if you need to save money cause you don't have much to spare, i could see just fixing the problem in the engine. but if you have some money to spend and some time (lets say its not your everyday driver) then i would say rebuild the whole engine. www.whifbitz.co.uk has engine parts. you can also do a search over the internet for different part dealers. other option is they have these engines for bid on ebay with low mileage on them.

if ur engine is knocking please don't drive it as it will create a whole lotta damage

you will need to replace your bearings and get your rods, crank, caps all measured to make sure they're within spec... you may be up for a new crank depending on how bad the knocking is and new mains and rod bearings... your reconditioner should be able to tell you what size you need

so basic parts off the top of my head

head gasket
rod bearings
main bearings
rings
crank (maybe)
rod on suspect cylinder (maybe)

and make sure in future you have oil in the engine ;)