Yea - there are truckloads of good and free plugins...
I have to say that I still use loads of freeware in every mix - and I have almost everything - All Sonnox, all UAD, Waves Diamond, Lots of PSP, Voxengo, Kjarhus. Lots of iLoks, Dongles and stuff are slowing down the project loading ;-)
I don't have links in that moment, but do a google search:
Digitalfishphones: Blockfish (Comp), Spitfish (Deesser) and Endorfine (Multibandcomp) as well as Dominion (Transient Designer) can be found in all of my mixes - sometimes they just blow away the $$$ Stuff...
Check Voxengo.com - not only loads of high-qualy and very useful plugins for free - even the commercial plugins are very cheap and highly professional in the same time. Voxengos Concept is just great - if you are a returning customer you get lots of discounts and stuff.
Kjaerhus Classic Collection is cool too... and free.
Then there are load of goodies from MDA, TBT, Silverspike etc ...
This & a modern sequencer (which usually comes with loads of usefull plugins as well) should enable you to create state-of the art mixes/recordings without any cost. These days there are even professional sequencer availeble for very little monay. Reaper... etc.