I have a lasco whirlpool 2004dc 2783 826062 where would i find inline heater

You can add an inline heater to any almost any jetted bathtub. Here is a link to site that sell all kinds of them.

It is always possible to add a heater to any jetted bathtub at any time.
What you need to find out that is if the tub is plumbed to each jet with rigid PVC pipe or flexible PVC pipe.
If it is plumbed in flex pipe then the Tee heater will be easier to install however if it is plumbed in rigid PVC then I would suggest a inline pressure heater that you will install in the water line any place after the discharge of the pump.
Here is a link to a installation instructions so you can see how all heaters are installed.
US Parts Center

You do not want to install any heater upside down because if any debris gets inside the heater pressure switch while it is running it will NOT shut off once the pump shuts off.


Rod
US Parts Center
888-521-6183

p, li { white-space: pre-wrap; }

Click on the link below and then under the Product Options use the drop down menu to choose the color of the item you need. You must match up the jets you have in your tub to what is shown online.

http://www.uspartscenter.com/index.asp?PageAction=VIEWCATS&Category=387

Go here and put in your model number.
http://shared.whirlpoolcorp.com/product_literature/search.jsp?siteCd=WHRCOM

look at the heater you have. it will say either Pressure Inline Heater or Vacuum Heater. The pressure heater installs after the pump and the vacuum heater will install before the pump in the suction line.

In looking at the spec sheet for this model, it appears that a heater is already installed at the factory. See this link:
http://www.us.kohler.com/onlinecatalog/detail.jsp?item=9737602&prod_num=1164-H&module=Bathing&frm=null

If the whirlpool isn't heating, the power to the heater, thermostat, and the heater itself should be checked.

you need to use a cleaning solution to get the bacteria out of the plumbing lines. suggestions: Jet Cleaner

lasco jets usually unthread counter clockwise out of the wall fittings

Sorry, the tub will have to pulled out to find out what is leaking so it can be fixed. There is just no other way UNLESS you can open up the wall on the blind side of the tube. (but its probably and exterior wall...if the house is vinyl sided, it can be done. If brick, you'll have to pull the tub). If you just wanted to convert to a tub only, maybe Bathfitters has an insert solution...