ok i want to learn pearl and do some php in linux with python as i know their compilers and interpretters are already installed but how to start, i mean where to find them where should i write the codes, mainly help me with pearl

by reading :-P
also you can download existing projects and read their code to help understand, but i would only advise doing so if you already have a basic knowledge of programming in general.

http://en.wikipedia.org/wiki/PEARL_(...ming_language)
http://www.irt.uni-hannover.de/pearl/pearl-gb.html

http://en.wikipedia.org/wiki/Python_...mming_language
http://www.python.org/

http://en.wikipedia.org/wiki/Php
http://www.php.net

Do you really mean Pearl? Or did you want Perl?

First thing that caught my eye- do you mean Perl or PEARL? They're both programming languages, but as far as I know they're NOT the same.

Second, learn one language at a time, not three.

For Python, there is an EXCELLENT book released under the GNU FDL that I'm reading called How to Think Like a (Python) Programmer available from Green Tea Press (iirc). It's short, but it explains things very well. Most books I've seen spend ten pages showing the exact same concept. How to Think Like a (Python) Programmer does it in about three.