Some of the best freeware lists for your needs:
- Gizmos freeware reviews: Provides useful comparison of various freeware tools sorted by reviewers rating.
- MakeUseOf – Windows, Linux, Mac: Another great collection of useful software (not necessarily freeware). Do check out their site for other categories like Android, iPhone, iPhone and such
- Addictivetips: A great blog with information related to useful software and tweaks.