On Day 2, give him the handkerchief after he falls and agree to let him give it back to you some day. Then, on Day 10, go back to the train station. Ba-BAM. Emmet.
through his stomach
Buy him with $300 using the computer.
Go To Train Station On The Second Day
While your in the past on day 2, go to the train station. He will trip in the cutscence and you give him your handkerchief. Ask him how he will return it and go back to the train station on day 10 and another cutscene will play and he will stay there.
Go to the future and buy him for $300 on the computer in the apartment. It will take a few days to get there, I'm not sure exactly how many.
the tea
You go to your room in the present/future and click on your computer then click firefox and click on Oz, he is $300 and he takes a few days to arrive, like 2 days, so sleep in the future and wait for Oz.
chocolate
wonderland days
No you can't. All the other androids are sold out, and Oz is the only one left. He's 300$, but you can use the cheat 'screwtherulesihavemoney' to unlock him.
in the appartment in the computer
He's in the Laboratory back in the future.