Who can tell me where can I get a good biography on the philosopher "Karl Marx"?

A number of excellent biographies can be found here:

http://www.marxists.org/archive/marx/bio/index.htm

That site, of course, has rather a Marxist perspective, so what you'll find is primarily laudatory. The standard 1918 Mehring biography of Marx, which is relatively balanced, can be found there, though:

http://www.marxists.org/archive/mehring/1918/marx/

You might also try David McLellan's recently revised study of Marx, now in its fourth edition:

http://www.amazon.com/gp/product/1403997306/ref=cm_cr_pr_product_top

Good luck!

The outgrowth of Karl Marx's philosophy is the most horrible suffering humanity has ever gone through. You couldn't be more wrong. The Creator of the universe became a babe in Bethlehem 2000 years ago. The proof is the fruitage for 2000 years afterwards. If that religion is an opium, it's the medicine that cures humanity of the cruelties of Karl Marx. Anyone who admires him is a fool.

For a criticism of marx-ism,see Popper's The Open society and its Enemies.

Everyone who works in a large organisation should read it to.

wikipedia

http://en.wikipedia.org/wiki/Karl_Marx

this is a very useful web..
hope it helps..