Planet Hulk doesn't have any tie-ins but its out in tpb and HC. If you like it a lot you might want to check out it's sequel, World War Hulk and/or the WWH spin-off Skaar: Son of Hulk which is really good.
I'm not really that knowledgeable on Wolvie or Spidey stories except I heard the "Old Man Logan" story line by Millar was really good.
If you liked Civil War you might want to try some more Millar stuff like Ultimates and Ultimates 2.
If you want to read some Marvel stuff that's more crime-drama street level superhero like Bats you should check out Bendis' run on Daredevil. After he left the book Brubaker took over and it has been great -- I would check out Bendis' run first for spoilers sake.
Brubaker also did an amazing run on Captain America which is still going on if you're interested in some action/spy type stories.
If you're into the sci-fi stuff like GL you should take Blader's advice and check out Annihilation. It was a big event with a bunch of Marvel's sci-fi/space characters like Nova and Silver Surfer. You can also check out Nova's ongoing that I've heard great things about.
They also made a sequel to Annihilation called "Annihilation: Conquest" that was really good. Another ongoing title that came from the aftermath of that event is Guardians of the Galaxy which I hear is extremely good as well.
Probably my #1 favorite book out right now is Incredible Hercules though. I just can't stress enough how good it is. It's action/comedy. Not too silly, not too grim. LOTS of action, great pacing, great dialogue, etc.
Hope that helps. I just tried to outline the main genres in Marvel comics right now.