I found the navigation really crappy as well. And they make yo wait through all this other intro crap.
Anyway, here are the instructions to find it
1. Go to
http://www.tokyoplastic.com/
2. Click the Japanese under "enter Tokyoplastic
3. click the square japanese flag on the right of the new window that opened
4. A chair comes up the in the middle. Click the Japanese on top of the chair
5. It now goes through about a 15 second animation resulting in an odd looking plant with weird toothed flowers on the end of each branch/vine. If you hover over the second one from the right in the tp left you will see that it says drummachine. That is how you know that you found the right one. Click the second one from the right.
6. Thinking that this will run the drum machine is wrong. It now goes through a 10second animation and then you will have to click the small square Japanese flag in the middle of the screen.
7. Thinking that this will also run the drum machine is wrong as well. It goes through about a 4 second animation and leaves you with an empty box at the bottom of the window. Click the empty white box.
8. You think that this will run the drum machine, well, you are wrong. It now runs about a 45 second animation with a box running with feet on it. The it does a TPX animation with the THX sound thing from movie theatres. It then leaves you with a small character banging its head on a drum. Click the Japanese writing on top of it.
9. It will then go through about a 30 second animation after which the drum machine you are looking for (I hope) will be loaded.
Don't ask me how I got through that navigation, but it worked.
Enjoy