You're not going to get any real free DDoSers, if you want a DDoSer then you will have to pay and buy it off HackForums.
No it's possible. You just can't get that stuff for free. People saying download free ddoser in description are trying to key log you. Don't get into it though because it's illegal and can get you into trouble.
Ddosing is the easiest thing ever. I personally know people who do it 24 /7. I personally hate it and am disgusted by it. Runescape servers are ddosed often aswell, as in particular worlds. Prior to F/T release again, w137/65 was ddosed everyday for 1 - 3 hrs. It can be done by a 11 yr old, provided they have $$, or provided they are smart enough to spread their botnet and or host a few shells on a dedi, which requires no $$, rather brains and effort.