No offense, but most Japanese people do not know how the visa and immigration system work.
Glenski speaks the truth.
I mean, not even one Japanese in my class nows anything about immigration, and even worst the teacher that in charge of my class don't know anything about it too.
So you will be staying there a month or two, right?. Are you that desperate for money? Part-time work won't even give you that much money, I bet everything will go byebye after you go for a yakiniku or something. Considering you that want to "mess around/touring", you won't even have that much time to work, maybe once twice per week. Which brings me back to the point I'm trying to make. Just bring enough money for your stay duration.
But, if you want to work just for the experience, I'm guessing volunteer work is OK? no?
<considering if you actually can get a student visa>
Most school are strict when it comes to dealing with immigration (since I bet they don't want to get on their bad side), so almost all school will have at least a 3 month no-work policy in place before giving you the permission to work.(which I noticed when I went school searching a year ago, even If you're already here 1 year+, when entering a new school, you still have to wait 3+ months)
Even if you Japanese friend says its ok, don't work illegally please. It's already hard for us gaijin student (that really wanted to come here to study) to get in Japan as it is.
The only reason I brought this up is, this week theres another idiot got caught working without a permit. His reasoning? "I don't know that you need a permit to work".
Not implying on anything, and no offense intended.
Well, we still don't know what kind of visa will you be on anyway.
Either way, just bring enough money and have a blast. Working, visa etc can really give you a bad headache you know. Just come and enjoy~