Mine

gcc -c SDLzilla.c -o SDLzilla.o -I"/sw/include" -I"/usr/include" -I"/usr/local/include"  
gcc SDLzilla.o  -o izilla -L"/sw/lib" -lSDLmain -lSDL 
ld: Undefined symbols:
.objc_class_name_NSApplication
.objc_class_name_NSAutoreleasePool
.objc_class_name_NSMenu
.objc_class_name_NSMenuItem
.objc_class_name_NSObject
.objc_class_name_NSProcessInfo
.objc_class_name_NSString
_CFBundleCopyBundleURL
_CFBundleGetInfoDictionary
_CFBundleGetMainBundle
_CFRelease
_CFURLCreateCopyDeletingLastPathComponent
_CFURLGetFileSystemRepresentation
_CPSEnableForegroundOperation
_CPSGetCurrentProcess
_CPSSetFrontProcess
_NSAllocateMemoryPages
_NSApp
_NSDeallocateMemoryPages
___CFConstantStringClassReference
_objc_msgSend
make: *** [izilla] Error 1