first of all, one question: how is it living in japan? Is it like we see in TV, a world full of gadgets and people with green and purple hair??? An what about the radiation? How has affect the life of Japan?

the capacitor is not necessary to be ceramic, although i suppose the one you got is ceramic. For the 30 LEDs with 12 volts supply, you will follow the 47 ohms resistor (you could use a smaller one as well if you want brighter LEDs). You need to have 10 rows, each one with one resistor and 3 LEDs. Each row will draw max 20mA, so you are right, 200mA is the max current.

Regarding the transistor, you could use any other transistor capable to power 200mA (AT LEAST 200mA). The ones you propose i have never heard of... ever! So i tried to find the datasheets. I found for:

C2542 - no datasheet found

K30A - no datasheet

C2655 - 1A. current is ok, hFE around 40: hmmm you may need to use smaller R1, like 2K2

C1815 - 120mA (no good)

A1015 - 150mA (kid's play)

So, go for the mighty C2655 with smaller R1, as you need lot of current for the LEDs. Here is a rough calculation for R1:

You need 200mA current, let me say that you could use 250mA. The transistor hFE is 40, so the base current must be 200/40 = 5mA

The base supply is 12 volts and you need 5mA. So, the minimum resistor you can use is (ohm's law):

R=U/I => R=12/5 = 2400 ohms. Close to this value is 2.2 kOhms (also we write as 2K2).