What Kind Of Album/Folder Do I Need?

Very nice!
As you expand, you can start to put like coins in their own pages, and eventually their own binders.
It's fun to watch it grow.
Sooner or later though, you'll get the bug to specialize in one series for a while.
It's a satisfying feeling to complete that first set.... even better than your first binder!
Good luck!

"Slipcover"? No I didn't. How does that work - like a platic sheath that slips over each page? Or like a bag the whole binder goes in?

I just ordered some 2.5x2.5 pages though. I got 2.5" cardboard flips for my silver eagles and dollars. I like the way they fit dollars better, because with the 2x2s I never could get the sides stapled closed all the way. I'd always see the rim of the coin exposed.

aaahhhh...

If you can't find a slip cover of the appropriate size, use a corrugated cardboard box of the nearest dimensions. You may find such an item at an electronic games or photographic shop, with the box thrown out in the trash. Just seize the opportunity when something that suits your needs becomes available.

I use a converted metal beauty case for two of my smaller albums, I found them at a church fate at the junk stall; they cost me $2.

12 pocket album pages made specifically for slabs will fit right into your new album.