I have discovered there are smaller official plug-ins besides the expansion on the TES site.

These plug-ins have stuff like bards abilitys (able to tell jokes, play music etc) a new dungeons, sounds, armor etc.

What I want to know is if this is free.

Are the smaller DLCs for Morrowind free? Or do they cost money?

They are free.

DLC=offical plugins=addons right? ive seen DLC used for expansions when i was under the impression it was basically cosmetic, or promotional addon content.

I'm not sure what you're trying to say here. What Indorilseeker and I are talking about are http://www.uesp.net/wiki/Morrowind:Official_Plug-ins.

so he ment the plug ins. i get lost when DLC gets used to cover everything lol.

Yes, he wrote specifically: "I have discovered there are smaller official plug-ins..."

Yea those are the ones I'm talking about.

Cool a few of the plug-ins look good, I'll be sure to download them, I'll get at least 2 or 3 hours of content. The other ones should add extra immersion.