so I heard that xdebug conflicts with other zend extensions such as APC, etc...
in light of this, are there other alternative php debuggers for netbeans available besides xdebug?
Unfortunately, the answer is currently "no". When Oracle decides to enable Zend Debugger support, I'll be all over it like a rash.
On the plus side, the Zend Debugger is the only extension I've had to disable to get XDebug working. APC works fine.
Xdebug does not conflict with APC. Only Zend's zend-extensions will cause issues, and otherwise it's most likely a bug that should be reported at http://bugs.xdebug.org.
APC + xDebug. So, probably you should not rely on rumors, but try it yourself instead.