Owner's manual, or FSM?
If you're after an Owner's Manual, you'll find just about anything you need to know, everything that's in the OM and more besides, here just for the lookin'. Fluid specs and such are on my site under the Tech Archives. You can probably find an OM on eBay if you pillage around a bit - I've been finding FSMs there back to 1965 or so.
If you want a Service manual, you've got a couple of options:
1) Go aftermarket - Chilton's or Haynes. I use my Haynes manual for propping things up (it's more use to me that way...) and I find that Chilton's is a good beginner's reference. It's nowhere near as detailed as an FSM (Factory Service Manual,) but it doesn't sound as though you're ready for one yet - so it's a good place to start.
2) Go OEM - FSM. These are spendy (even on eBay, expect at least $50-100 for the thing unless you get lucky, and you can find reprints through outfits like Books4Cars,) but are well worth it. Detailed troubleshooting information, detailed service information, very few errors (the only one that really stands out in my mind is that you do not use GL-5 in an AX-15, you use GL-3,) but they're more for experienced wrenches. Dealership mechs use these. The FSM set for your 1989 will be either two largish books or the two largish books and two smallish supplements - depends on which set you get.
Also, if you look for an FSM, you can use a 1990 as well - since that will be functionally identical to your 1989. 1987-1988 will have small but significant differences (AMC production vice ChryCo,) 1984-1986 did not have the inline six available, and 1991-up use different control systems (meaning different wiring, different sensors, ...) ChryCo didn't make many changes between 1988/1989, but no sense in confusing yourself if you're not expecting it and you're inexperienced.
As far as selling you one - sorry, but none of mine are for sale. They're all "reference material" for Works in Progress... Still, if you need anything specific, I'd be happy to help you!
