I think there are 3 main lines of Marvel action figures:
1\ Marvel Legends
Mainly 6 inch by Toybiz (2002-2006) and Hasbro (2007-2013). They have quite a few variants (chase) and Build-A-Figure (BAF) collections which are very popular. You can read more and check their list of releases in Wiki. Marvel Legends - Wikipedia, the free encyclopedia
Thanks! What about Super Hero Squad? Are they done?
It's still alive...kinda'...
The have 4 figurine boxed sets of The Amazing Spider-Man and the Avengers Movies under the SuperHero Squad "banner"...but since the show has run its course, I don't think it has much time left....