Welcome back to the world of Pokemon, and welcome to SuperCheats. I'm Warrior13 (you can call me Michael), the local Pokemon Master / Know-It-All. I'd be glad to answer your questions:
1. You can find out your Friend Code in Black 2 and White 2 by accessing your Pal Pad. It should be found in the Key Items section of your Bag. Once you open it, it should give you the option to view your Friend Code.
2. It is possible to Legitimately Obtain the Original 150 (151 if you count Mew) through Trade. However, you might want to run the Pokemon through a GTS website (such as PokeCheck) to make sure the Pokemon is actually Legit. There are a lot of fakes out there.
3. When it comes to EV Training, you really need to start with a UT Pokemon (Untouched Pokemon; A Pokemon who hasn't battled yet). You see, your Starter Pokemon has already been earning EVs (Effort Values). It is best to start with a fresh, UT Pokemon. As a reminder (you probably already know this) a Pokemon can have a total of 510 EVs (508 really because 510 cannot be divided by 4). Each Stat (Such as HP Attack, Defense, Special Defense, Special Attack, or Speed) can have a maximum total of 255 EVs (255 doesn't do anything different than 252, so go with 252). Most Pokemon you see (not all) that have been EV Trained will probably have 252 as one stat, 252 for another stat, and 4 or 6 for the final stat.
4. Besides some areas looking different, the two games are basically the same except for the Legendary Pokemon you will be able to find. In Black 2, three of the Legendary Pokemon you can catch are Zekrom, Latios, and Registeel. In White 2, three of the Legendary Pokemon you can catch are Reshiram, Latias, and Regice.
5. If you ever need some Pokemon, just post here: http://forums.supercheats.com/video-games/pokemon-trading-forum/135083/Warrior13-s-5th-Generation-6.htm?page=1 That is a link to my Pokemon Give-Away Shop. I will give you any Pokemon you need in exchange for any other Pokemon. As for Battling, I really only battle on Pokemon X / Pokemon Y (the newest Pokemon Games for 3DS).
I hope this information helps you, and I hope you stick around the site.
« Last edited by Warrior13 on Feb 20th 2014 »