Whether to get start with BTC, LTC, DOGE or any other cryptocurrency, the correct, easiest and safest way is to visit its official site.
So the following will show you the official sites of BTC, LTC and DOGE, which are my best 3 favorite digital currencies:
1. The official site of BTC
Bitcoin (bitcoin.org) — Which offers everything you need to know about BTC, such as what it is, how to choose your wallet, where to buy it, so on and so forth.
2. The official site of LTC
3. The official site of DOGE
Dogecoin (dogecoin.com) — Which offers desktop wallets for your Windows, Mac OS X and Android devices as well as an online wallet for your browsers.
When BTC, LTC and DOGE are becoming more popular, there will be more scam sites, wallets, mining tools and even some other things, so the official sites mentioned above are very important, and you'd better only use the wallets and mining tools recommended by them.
Besides the official sites, Wikipedia will be another ONLY MUST-HAVE site for you to get start with BTC, LTC and DOGE.