m2rt

Greetings, I am new to this forum and don't mind if I have noobish questions. Everybody will start as a noob. Now, about my problem. I installed Mangos and am in the phase of getting data files + client. Where exactly I can get them? I understand that from original wow client? Where can I buy/download original wow client? If I buy the client is it legal to distribute it as my server client? I guess not. But how can I make it so that even noobs can get to my private server? Thanks!