duckie- welcome to the forum- when you get a minute, stop over by the intro thread, say howdy, and tell us about yourself. We have a few other ladies that hang around- they pretty much cuss, spit, and drink like the rest of us, but they are more genteel when they do it.
Parts and pictures- Hoo boy! First, get real good at Google. A lot of gunmakers have owner's manuals on their websites. Also visit this one, and copy it to your favorites page (and if you use his stuff, contribute a buck or two to keep the lights on) http://stevespages.com/page7b.htm
If the maker is still in business, they would be an obvious first choice. gunpartscorp.com is the site for Numrich- used parts (no receivers) for a LOT of guns. Brownells is a good source for a lot of things, and Dixie Gun Works for muzzleloader stuff. Send all of them a copy of your FFL, you get a discount from them.
Disclaimer- I am not a smith- am a hobbyist, collector, and long term C&R FFL holder- but wind up looking for the damndest stuff to restore older guns I am working on (any seen a spare aperture sight for Mossberg 152 lately?)