Obviously I'd recommend taking your car to the track and avoiding this kind of behavior on public roads. With that said, as long as you're not doing it for prolonged intervals, and you're only doing it on wet pavement, there won't be too much abnormal wear caused by occasionally hanging your tail out. Reagrdless, I would recommend attending a local autox or HPDE event to learn how to control your car in a safe environment (it's also really, really fun).
As far as extra wear goes, this will usually occur from the excessive heat you'll be building in various components, which almost always increases wear on that component. Drifting usually involves revving the engine up into the higher RPMs to keep the tires spinning. This will increase oil and coolant temperatures, as well as increasing the demand on the oil pump. If you're low on oil or pulling higher than normal G forces, you could end up starving your oil pump and preventing lubrication to vital engine components.
Going back from there, depending on your speed, your transmission and differential will be spinning at or below freeway speeds, so there won't be too much excessive wear there. Depending on the type of tire you're using, extra heat will make the rubber softer, increasing grip, but also increasing the amount of rubber that will be transferred onto the pavement (this is why drifting or doing a burnout on dry pavement will leave tire marks). Once the rubber exceeds its peak operating temperature, there is a STEEP decline in performance and longevity, so if you pass that mark you will be doing a lot of damage to the rear tires. As far as the suspension/wheel bearings/lugs etc, if you're on wet pavement, you'll likely be putting less stress on these components than if you were cornering hard on dry pavement, so no real worries there.
If you're pulling the ebrake to initiate the drift, the shock of immediately stopping the rear wheels/axles/diff/driveshaft/transmission could damage a number of components if they are not properly maintained, so I would not recommend doing that. If the car is equipped with traction control that you can turn off, some systems will still individually apply the brakes to keep the car somewhat in control, which would overheat your brake pads or fluid if done for too long.
TL;DR: Take it to the track. It's really, really, really fun, much safer, and much cheaper than the ticket and/or wreck and subsequent insurance charges you will eventually be paying once you run out of skill.