OK...
First, you can run your primary and secondary from any of the three DC's... however, I recommend you use one BDC as a primary and the other as your secondary.
Regardless...
The WINS address's on the primary should be the primary's IP address. Yes... both the primary and secondary WINS address on the primary are supposed to be the same IP address. Do the same on the secondary WINS server... both WINS address are the secondary servers IP address.
If you do anything right the first time you set up WINS.... do the above. Failure to do so will cause you lots of headaches.
Second... In your DHCP scope you can identify your WINS servers so that clients will automatically get them at logon. It is not automatic when you set up the WINS servers... you have to go into the DHCP server properties, the scope you have set up, and identify the addresses of the WINS servers. Then, your clients will only need to be setup to use DHCP.
Recommendation: Get your company to subscribeto Microsoft Technet... or get some older copies from someone you know who has a subscription.