I studied the Japanese language in 東京 for 18 months as a teenager and came out with 日本語能力試験二級. My experience is pretty limited, I'm out of practice and I'm happy to be corrected by anyone (it's the best way I know to learn).

That said, for my length of study I have probably an above-average amount of conversation practice and may be able to help out with some more obscure matters of etiquette and word/grammar usage, especially from the 関東 region.