Welcome Nick,
I agree with slo318TI, you likely have an oil filter housing leak. Use some brake cleaner to clean off any leaked oil and go drive around for a day. You should then be able to see exactly where the leak is coming from. If it is the oil filter housing you will need more than just the gasket mentioned. There is a 'bushing' as well, which is really just a check valve with an o-ring at each end. Here's the kit I've put together.
http://shop.bimmerbum.com/products/3...and-gasket-kit It's not a difficult job to replace the oil filter housing and bushing but a lot does need to be removed so consider replacing things like belts, pulleys, doing an oil change at the same time, air filter, intake boot, and don't do all that work without replacing the coolant fitting on the block right behind the oil filter housing.
http://shop.bimmerbum.com/products/3...1-53-1-714-738 While your at it, do the coolant fitting on the back of the head as well. This little fitting is likely responsibly for most M44 overheats.
http://shop.bimmerbum.com/products/3...1-53-1-743-679 If you have any questions, just post them up. This is a friendly group, always willing to help.
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