Cant find Macbook Pro on PC Network and vice versa

Hi, I am a new Mac user and am used to PCs that are very easy to setup on a network. I have tried to setup my Macbook Pro so that my PCs can see my Mac and vice versa. I have 2 PCs that are running Windows 7 and have a Home Network going. The 2 PCs are seeing each other but they are not seeing the Mac. On the Mac when I try and access the 2 PCs it just says "Connection failed, check the server name or IP address", but my server name is correct and my IP address is correct. Any advice please as I am about to sell this Mac and go back to PC. Please help!