g++ shared library not found same directory with -L - c++

Question

I just cant see what Im doing wrong here:
Q. Why is my library not being found by g++ when compiling the program with a shared object?
Im trying to include a shared library to my c++ program:
g++ -fpic -c sha.cpp
g++ -shared -o libsha.so sha.o
g++ main.cpp -o main -L. -lsha
where sha.cpp and sha.h are the library files and main.cpp is my program.
Ive tried the same with static library which works find:
g++ -static -c sha.cpp -o libsha.o
ar rcs libsha.a libsha.o
g++ main.cpp -o main -L. -lsha
The platform is cygwin on windows and here is the output:
rob#pc /cygdrive/c/src/a
$ g++ main.cpp -o shatest -L. -lsha
/usr/lib/gcc/i686-pc-cygwin/4.3.4/../../../../i686-pc-cygwin/bin/ld: cannot find -lsha
collect2: ld returned 1 exit status
Ive read all forum posts but the library is in the same folder!
$ ls
libsha.so main.cpp sha.cpp sha.h sha.o
The reason im doing this is that on another platform, a library is being created whereby when one object is called, it works, but the app crashes when the second object is being constructed. Im doing the above as a simple test! (annoyingly not so simple).
source files below:
main.cpp
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>
#include "sha.h"
void *thread_one( void *ptr );
void *thread_two( void *ptr );
main()
{
pthread_t thread1, thread2;
int iret1, iret2;
/* Create independent threads each of which will execute function */
iret1 = pthread_create( &thread1, NULL, thread_one, 0);
iret2 = pthread_create( &thread2, NULL, thread_two, 0);
/* Wait till threads are complete before main continues. Unless we */
/* wait we run the risk of executing an exit which will terminate */
/* the process and all threads before the threads have completed. */
pthread_join( thread1, NULL);
pthread_join( thread2, NULL);
printf("Thread 1 returns: %d\n",iret1);
printf("Thread 2 returns: %d\n",iret2);
exit(0);
}
void *thread_one( void *ptr )
{
printf("Run thread_one\n");
CObj1 obj;
}
void *thread_two( void *ptr )
{
printf("Run thread_two\n");
CObj2 obj;
}
sha.cpp
#include <stdio.h>
#include <stdlib.h>
#include "sha.h"
CObj1::CObj1()
{
printf("CObj1\n");
a = 10;
printf("CObj1: %d \n", a);
}
CObj2::CObj2()
{
printf("CObj2\n");
a = 10;
printf("CObj2: %d \n", a);
}
sha.h
#ifndef LIB
#define LIB
class CObj1
{
public:
CObj1();
private:
int a;
};
class CObj2
{
public:
CObj2();
private:
int a;
};
#endif