For the fuse block layout check in either a factory service manual, a Chilton manual or a Haynes manual. If you don't have one the Chilton or Haynes manuals are often available at a library.
On some cars there is a sticker in the engine compartment with a belt diagram.
You can find fuse block diagrams for your 1989 Chevy Celebrity in either a factory service manual, Chilton manual or Haynes manual. If you don't have a manual your local library may have a Chilton or Haynes.
Looking in my factory service manual for a 1989 Chevy Celebrity I found no reference to an accessory relay.
You can find a 1989 Chevy front axle diagram at most Chevrolet dealerships. Most local libraries will have Chevrolet service manuals with the front axle diagram.
You can find the wiring diagrams for a Chevy Celebrity in either a factory service manual or either a Chilton or Haynes manual.
Chilton manuals don't include wiring diagrams, but the Hayne's manuals do. Also, if you have a well stocked public library, check the manuals there.
you might try www.haynes.com
A complete diagram is available at MOTORLIT.COM.
You can find a fuse block diagram in either a Chilton manual, a Haynes manual or a factory service manual.
most auto parts dealers have or can print out a routing diagram.
Prices tend to vary with suppliers, there does not seem to be a standard price. When I need parts for my Chevy Celebrity I survey the local sources and buy the best deal I find.
you might try www.haynes.com