The best place to start looking for a manual for a McCulloch Titan 57 chainsaw would be mymowerparts.com, which has an extensive list of downloadable manuals for McCulloch products. The list is so long, it might be handy to have the product ID code to hand!
The site store.chainsawr.com claims to offer the largest collection of used chainsaw parts in the world, and has a large selection of McCulloch spare parts, having bought out a local dealer. Take a look to see if they sell old manuals as well, or perhaps they can offer you advice.
You might also try online user forums such as doityourself.com or lawnandgardenmanuals.online.com. If you can't find what you're looking for, join up and post a question about McCulloch Titan 57 manuals.
YouTube can often provide help too, and users often post demonstrations or reviews of outdoor equipment, such as this film of a McCulloch chainsaw repair:
