Your local homebrew wine and beer supply store will have a variety of tapered rubber stoppers. You'll be able to find a fit for any bottle you have. Be sure to buy the solid ones, and not the drilled ones.
The flip top Grolsch bottles really are nice. Also, I like the Fullers 1845 and ESB bottles. They are 500 ml, and very heavy glass. They aren't flip top though. You'll need the rubber stopper.
For half gallon sized brown glass of nice heavy weight, use brew pub growlers.
Many beers are sold in 22 ounce bottles. Those work great too.
WIne and champagne bottles come in 750ml and 1 liter size.
It's easy to get a variety of different sized brown bottles at your local liquor or grocery store.