Networking References

Hi, I am a newbie to the IT and network management field. I have a few years of experience under my belt with designing and maintaining fairly advanced networks but I have reached a knowledge barrier when it comes to tweaking networks for max speed, throughput, bandwidth, etc... I would also like to know more about monitoring and logging activities on my network to find problems and security holes. I have a network that is being bogged down by only 25 pc's and I havent been able to find the problem. So I find this to be a really good learning exercise.

Can anyone suggest good reading material for this? Im looking to purchase a few good books to enhance my knowledge. Please dont suggest any basic or beginners books. I am looking for advanced material.

I am working with windows networks.

Thanks in Advance!