TMNT 2K3 On DVD
 

So, I'm trying to catch up on my DVD collection. These are the DVDs for the 2k3 series that I know have been released:

In seasons:
Season 1 (Part 1)
Season 1 (Part 2) (I know this one isn't out yet)
Season 4

Non-season DVDs:
Volume one
Volume two
Volume three
Volume four
Volume five
Volume six
Volume seven
Volume eight
Volume nine
Volume ten
Volume eleven
Volume twelve
Michelagelo's Christmas Rescue
Volume thirteen
Volume fourteen
Volume 3.1
Volume 3.2
Volume 3.3
Volume 3.4
Volume 3.5
Volume 3.7
Fast Forward: Future Shellshock

My questions are: Are there any episodes missing? Are we expecting them all to be released in seasons or should I go ahead and buy whats already there?

Well, most likely they will (do Season-Part releases for all of it).

On the DVDs released so far. The 'Season 4' DVD that's out is only about half of the actual Season 4 (the rest being on some of the 3.# Volumes). And the real 5th Season hasn't been released here (though most of the episodes are on an Australian DVD Set).
Then, of course, the Volume releases put episodes in a mixed order (starting with Vol. 11).

Why did they do it that way? I had to have the Wikipedia DVD release list in front of me at all times in order to know which DVD to pop into the player so that I could watch the episodes in order. I got all but one of the DVDs for 99 bucks from someone on Ebay- best bargain ever. Getting them one by one would have been time consuming and very expensive.