A mini exercise bike can be bought online at amazon and may cost around $150 for a new one. This however does not include the shipping price. Pictures and other information about the product is clearly labelled.
I think you mean where and the answer is in a mini bike store.
You can buy a recumbent exercise bike at Wal-Mart. You can purchase them online or in stores.
One can buy a mini dirt bike from the local bike stores. Sometimes local community auctions also feature variety of mini dirt bikes for very reasonable price.
look on Craigslist Virginia
india
Often it is possible to buy a mini moto bike at a regular motorcycle salesman. You go to the salesman and ask him for a mini moto bike. Either he has one in his assortment or he asks his delivery man for a catalogue which he can show to you.
There are quite a few exercise bikes to choose from for under the cost of $500. A great exercise bike to buy for under that price would be the Schwinn 220 Recumbent exercise bike.
You can be any age to buy a mini dirt bike in the UK wether your 6 or 16 you can buy one but you are not allowed to ride one on the road at any age in the UK you would have to take the mini dirt bike to a dirt track and you can book weekly sessions with them so you can go like 3 times a week if you wanted to. So you are allowed to buy a mini dfirt bike at any age you just can't ride it on the road. i hope that's a help.
monsterscooter parts has them on the internet for $42
http://www.minipocketrockets.com/r32-4-stroke-super-pocket-bike/
form_title= Exercise Bikes form_header= Get in shape with an exercise bike. What is your budget for an exercise bike?*= _ [50] What type of features would you like?*= _ [50] Do you want the bike delivered?*= () Yes () No
Buy a new one.