welcome R0zzer
as Wayne said, this board is an incredible source of information, even beyond the scope of the DSP boards alone.
When you check out the devices forum take care at the dates, as some 'old' stuff frequently pops up later again, which might be confusing if the supplier has left in the meantime.
'Old' doesn't mean 'outdated' - most of the devices are still very useful, but developers had their learning curve, too.
Which means that more recent stuff exploits the DSP resources (shamelessly) up to the limit.
People sacrifice polyphony in favour of an improved sound - it's the difference between very good and excellent
Since the developement system is pretty 'expensive', there are not so many free devices (compared to VST).
But afaik all commercial plugins have demo versions available and are reasonable priced.
Honestly, it would be too much to demand that stuff for free.
2 exceptions come to my mind:
#1 is Adern's KickMe - as the name implies a (THE) bass drum.
The developer donated it as an excuse for a delay in the Flexor package release - a practice worth being adopted by any software suppliers btw

#2 is the Saturn synth as the result of a review of the developement system in German Keyboards mag. Again great idea to review and release.
But don't dig into too much too fast.
Take a little time to exploit each unit - there are often hidden gems appearing by subtle tweaking

...and most of all have fun !
cheers, Tom