You may buy bitcoin at many places, but how to chose the perfect one?
Everything depends on few criteria: location, preferred payment method, the level of anonymity and bitcoin rate.
We'll start with international exchanges.
Coinbase - supporting many countries worldwide, accepts bank transfer, credit cards and more payment options. Furthermore, it probably most popular Bitcoin exchange platform available right now. However, privacy is equal to zero, because for any actions you may provide your documents.
Full Coinbase Review
Cex.io - huge list of supported countries, deposits can be made by credit card or bank transfer. Cex.io is located in UK.
Full Cex.io Review
Exmo - a lot of deposit methods available (incl. Perfect Money, MoneyPolo, Advcash, Neteller, etc.). Supports many countries, however USA isn't supported. In addition, trading platform is provided.
Full Exmo Review
Coinmama - purchase may be made by credit card only. However, the list of supported countries is very long. So it's convenient place to buy coins with a card.
Full Coinmama Review
LakeBTC - probably the longest list of deposit/purchase methods supported. Works in many countries also, including USA (still New York is excluded). Sometimes Bitcoin rate could be smaller.
Full LakeBTC Review
Changelly - despite Bitcoin support, it allows to trade tons of other cryptocurrencies. Purchase can be made via Credit Card. The list of supported countries is long enough also. However, crypto rate should be much lesser than it usually is.
Full Changelly Review
Europe Exchanges
LiteBit - one of the biggest Bitcoin exchanges in the Europe. Supports not BTC only, but most biggest cryptocurrencies as well. Payment methods includes SEPA, MyBank, Sofort, and many other. UI is great. Great place for Europe residents acquiring bitcoins.
Full LiteBit Review
BitPanda - fast growing bitcoin exchange located in Austria. Supports deposits by credit/debit cards, Neteller, SEPA, etc, etc. Have many other great features too.
Full BitPanda Review
Coinhouse - France based bitcoin exchange. Allows deposits via credit/debit cards, Neosurf and bank transfer (not for everyone). Fees could be better, however security is amazing.
Full Coinhouse Review
BitBay - BitBay HQ is located in Poland. Besides exchange option, it has trading platform as well (with many supported currencies). Privacy is better than its competitors. Deposits may be done via credit card, wire transfer and more options for residents of Poland.
Full BitBay Review
Australia Exchange
CoinSpot - one of the best Bitcoin Exchanges in Australia. Supports tons of cryptocurrencies including Bitcoin for sure. Deposits can be made by POLi, BPAY, and some more.
Full CoinSpot Review
I'm still researching for best Asia exchanges (apart from LakeBTC which works great in Asia countries or Exmo which supports these countries also) including countries such as India, Philippines, etc.
Disclaimer: use these exchanges on your own diligence and judgement. Double-check them before registering, as well use Google to find more testimonials and ratings