My cousin who lives in Germany and I owe a home in Michigan. We have renters who would like to purchase it on a land contract. My question is can I have a land contract drawn up between me and the tenets and file it legally or does my cousin also have to sign it?

Depends on how you are listed on the deed.
But my guess on how it most likely is listed, you both should sign. It should not be a real issue, to send him a copy and he return it.

I would also note that on the contract, who much down payment are they going to make?
Have you addressed what happens in the contract if they default, ( like it converting to rental)
Have you addressed the issue of payment of taxes and house insurance. Remember you actually still own it, till they pay it off and you transfer ownership.

It is needed that you keep insurance on it, and I would advise you pay the taxes also. They should pay an escrow each month toward those costs. Failure would also be default.
If they want, they can still buy renters insurance, Remember they do not own it, till it is paid off.

Next what about repairs, it has to be addressed, what if the air conditioner goes out in 3 weeks. What if a storm blows off all the shingles?
What if they ruin all the carpets, tear out all the pipes and take off without making two months payments, Does the down payment given cover all of this ?

As Chuck said, it should not be difficult to send your cousin a copy for his signature. You could mail it, fax it or scan and e-mail it.

Another alternative is for your cousin to sign a limited Power of Attorney, giving you right to sign for him on a contract of sale for this property.

But I urge you to have a Real Estate attorney draw up the contract to make sure everyone is protected.