They can found by clicking the thumbnail to the left or the links below. More are coming shorty.
Years
Sonic HQ Encyclopedia

SHQ Search

So we have a new directory

Super Top Carnival Contraption Now With Hedgehog Maiming Action
Not Enough Rings

Hasn't updated in a long while and probably won't update anymore period. Oh well.
Sonic The Hedgehog 239 Preview Pages Up
Sonic The Hedgehog # 239 Previews
Want to read the full issue? You can get it here!
New SHQ VS Archive SHQ
This is a comparison chart of the main differences between this and the older version of the site at archive.sonichq.net/newsite Green boxes denote that the user experience will likely be better while red boxes mean user experience will be weaker. Ø means that it is missing. Even still, the Archive site is still a vital portion to this site. Note that a lot of the sections won't make an appearance on the new SHQ mainly because other sites just do them much better and our content isn't stellar to begin with. Like Fan Fiction.
New Coat Of Paint
Announcing New Music Section!

You can find it here. It contains all tracks from SA, SA2, Sonic Heroes, Sonic 2006, Sonic Unleashed, Sonic Colors and Sonic Generations. More is definitely coming! You can search out individual tracks or even search by artist. Music is streamed through your browser. It even works on smartphones. No flash required.
Enjoy!
Comic Section Revamp

I'm happy to say that the Comics Section has been redone with more HTML5 in mind. I hope this will improve the user experience! You can scroll through using your mouse wheel, the mouse itself and even the arrow keys on the keyboard. Note there are still some comics are missing from the database and comics are still being added.
Sonic The Hedgehog 237 Preview Pages
We're testing a new experimental feature by offering the preview pages officially released in a HTML5 format that modern browsers can take advantage of.
Sonic The Hedgehog # 237 Description & Preview Pages
Want to read the full issue? You can get it here!
Remember the old Sonic HQ?

I mean the really old SHQ. Sonic HQ of years past.
Chances are you haven't seen it in a while! Special thanks to Andy for all the files!
Announcing Midis Section Return!
This Just In!

Strange equine creature trapped in colorful rectangular room with no way out! Probably wants some hugs.
Rescue workers are running to find strategy guides to assess the situation.
Reintroducing Games and new Sonic HD section
Oh yeah, also testing a new layout.
Possibly Stupid Question
Sega Launches Europe Sonic Merchandise Site

You can check it out here: Sonic Merchandise. It's just Europe for now but they say an American release will be soon to follow.
Episode 2 Logo Announced

It's becoming more and more obvious Tails will be playable in Sega's next installment to Sonic 4 but remains to be known is the scope of his play-ability. Will it be optional a la Sonic CD Rerelease/Sonic 2/S3&K?. I'm betting on optional. Sega has learned its lesson.
Source: Sega Blogs