If it's on the driver's side only and begins near the accelerator and the center panel, it's coolant. Coolant can become dirty over time and if not changed. If it is coolant, it could either be a faulty heater core or heater intake valve, which is located in the center dash, or simply a torn coolant hose attached to these parts. Your "COOLANT" light should have turned on on your CHECK panel long before you noticed this leak, and your temp gauge should go up when the car is operating. Coolant steam typically fogs up your interior as an early sign before coolant begins to leak in this area.
Word of advice: if you can't do it yourself, do not trust anyone other than a BMW certified tech for this kind of job. Anyone else will cost you more money and could easily damage it further because they don't know what they're doing.
Thanks for the answer and you are so right; it Was a Coolant leak from a faulty heater core, and I Did end up having to take the car to an certified BMW mechanic, very expensive. However my car was fixed to my satisfaction and it runs better than it has for years!
Yeah, BMW Certified will always cost more, but you won't have to take it back. I tried to do it the cheap way, seeing how it wasn't that big of a repair (I honestly don't know how they come up with "7 hours labor" when there are folks that can do it in 2), but lost money because they only made it worse.
It's a bummer that this site doesn't have more E30 enthusiasts to answer your question sooner! If you still have your Bimmer, try BimmerForums.com or E30 Zone on Facebook. If you work on it yourself, try PelicanParts.com or RockAuto.com
I'm glad you got it fixed!