Topic: New here and thinking of starting a collection

Oh ok, I've found one for like 12 bucks.

I'd beware of cheap third-party Expansion Paks. I've had a couple and they were crap.
The EP was needed for Majora's Mask and DK64. The bad EP had a habit of occasionally killing the sound which would consequently, in the couple games I tried including even the non-enhanced Super Mario 64, make the game lock up the game the next time it tries to change the music (such as entering a new area). (that's something probably familiar to some people who had played certain unofficial SNES emulators )

Yeah I'm fully aware and staying clear. I'm bidding on one that is 12 dollars and it's an original Nintendo pack.

I've seen the third party controllers that look exactly like the original, are they any good? Or just find OEM?

Garage sales, flea markets, thrift stores, and Goodwills are all hit and miss... VERY hit and miss, but it's really worth it when you find a big box full of classic games. I find games nearly every Saturday morning. It's an easy way to buy and sell with a profit too if you keep an eye out for non-gaming items.
Also, most flea markets I've been to will have 1 or 2 game specific booths. Watch out, lots of people like to upcharge for games from popular series like Mario and Pokemon, but they often overlook some hidden gems.

The N64 is a great system with several classics. So, congrats on picking that up.

If you decide to start collecting stuff for the Gameboy, does it HAVE to be the original Gameboy? If not, I'd strongly consider a Gameboy Advance. I just picked up a GBA SP recently for around $30 and it plays GB and GBC games as well. Plus, in my opinion, the GBA library is outstanding.

@OneBagTravel: Flex!