A quick followon to mention is there’s a number of good places to find and buy DAW plugins. The most central are probably KVR Audio and Plugin Boutique.
As advice: never buy plugins at full price if you can avoid it. They go on sale all the time for drastic discounts.
Splice also has a rent-to-own system for some of the more expensive ones that helps make them affordable:
There’s also a lot of free plugins out there.