Networking a PC and a Mac

Hi,

I have a iMac and a Laptop running Windows7.

I wanted to create a network between the two so i can share files etc. I have setup Windows sharing etc on the Imac. Both are on the same workgroup.

I am able to easily access the PC from the Mac.( I can access files that are stored on my Laptop witjout any problem from the Mac)

However the Mac does not even show up when i click Network on the PC.

Not sure what I am doing wrong.

Any and All help will be appreciated

Just for your Info
Laptop is running Windows 7 Ultimate edition
Mac is running Snow leopard 10.6.3

thanks