help server bieng ddosed

[Jovial]

well my server is being ddosed
i am not a host but i think hosts now how to prevent it
can anyone tell me a way
from pat 1 week i am having this problem
pls don't recomend high costly script maximum i can afford $25
can anyone help to find a script

[Megaphile]

http://www.linuxsecurity.com/content/view/121960/171/

[Wojtek]

http://deflate.medialayer.com/
Install what