Here are some ways you can buy Bitcoin, Litecoin, Namecoin, Peercoin, using government issued money or other cryptocurrencies. In general, the easiest way to get any cryptocurrency is to first buy Bitcoin, and then trade for it.
1. Buy Bitcoin in America Using Coinbase.com
Armed with only a bank account, you can buy Bitcoin from Coinbase fairly quickly and easily. Bitcoin has instant verification with Chase bank, so it's the recommended choice if you have a few bank accounts. If you can't afford a full Bitcoin (roughly $1000), don't worry, you can buy portions of a Bitcoin. Coinbase will sell you as little as .01 of a Bitcoin, for about $10.
2. Buy Bitcoin and Ripple in America or Elsewhere Using Bitstamp.net
Bitstamp works similarly to Coinbase for Americans, but Coinbase is slightly faster in getting people set-up. Bitstamp, on the other hand, can help you out whether or not you're in America. You can also use Bitstamp to purchase Ripple if that's something you're interested in.
3. Trade or Daytrade Bitcoin for Litecoin, Peercoin, Namecoin, Novacoin, Terracoin, Primecoin, and Feathercoin at BTC-E.com
If you're interested in trading, you can trade Bitcoin for the all the aforementioned coins at the most popular Bitcoin trading exchange, BTC-e. I don't recommend putting cash into BTC, as you will have to use an international wire transfer and I have seen many complaints in the chatroom on the site regarding depositing cash. In any case, the site is by far the fastest, best way to trade cryptocurrencies on a daily basis. If you are looking to day trade cryptocurrencies, this is the best place where anyone can do it, though some say MCXnow is truly the best, but that site is currently not allowing new registrations, nor is it functioning. BTC-e is very fast and has a lot of volume. As far as I know, it is the only place where day-trading is possible at all in terms of volume and transaction speed.
4. Trade Bitcoins for Any and Every Cryptocurrency at Cryptsy.com
As a quick trading platform, Cryptsy is virtually unusable, but if you are looking to get into some of the smaller, obscure cryptocurrencies, Cryptsy has it for sale. The list is to long here, but you can see the full list on their homepage.
5. Trade a Huge Variety of Cryptocurrency at Decent Speeds (but Low Volume) at BTer.com
BTer boasts a robust list of cryptocurrencies, but it lacks the volume for daytrading. Still, it does seem to be a bit faster than cryptsy, so you might be able to move some money around here, at least in the popular markets like BTC/LTC.
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