Welcome to the hobby of model railroading.

Here are the definitions of the words you are looking for.

Siding: A track arranged paralell to the main track so that it may permit the passing of two trains. Can be single or double ended.

Spur: Similar to a siding. Generaly ends at some point not adjacent to the main track. Often used to serve industries with rail acess.

Fiddle Track: Purely a model railroad function. Is a track or small grouping of tracks arranged in a location to permit the changing and rearranging of train consists by removing cars from the layout and bringing new ones in from "off layout."

Staging Track: Also a model railroad function. A track that allows to trains to be staged in an order so that one may conduct an operating session. Permits a train to come from Somewhere and go to Somewhere. Often used to represent desitinations off the modeled portion of the layout. Can be used in conjction with fiddle tracks.

Switching Lead: The arrangment of track and switches so that acess to yard latter tracks can be obtained. Found only in yards or large industries that require multiple spurs. Some of the largest industires. Like steel mills are lage eneugh to reqire their own rail yards. and hence several switching leads can then be found.

I will look to see if I cant find some glossary of model railroad terms. But it may take a while. In the mean time, I am glad I could be of assistance.

Man if your biggest irritant w/the hobby is the language you are doing good! Just kidding.

I know how irritating it is to have a question answered by someone giving you a web address so I wont do that. Having said that, I will tell you that the internet is an INVALUABLE tool for todays Model Railroader. This is true in a wide variety of ways. From shopping to research to, just like you have done, networking- it is another reason why this is such a beautiful time to be involved in this hobby. You may want to start a bookmark page of websites. One of your first ones (other than this one of course) should be WWW.NMRA.COM. If you haven't checked it out, go there! THey even have a glossary

Okay, lessee
Siding: Real railroads usually consider a siding as an auxilliary to the main line. Here traffic can be diverted for a variety of reasons to allow the main to remain clear. This promotes the efficiency of the main line.

Spur: these are generally task or industry specific tangents of the main line. Often stub-ended(dead end), they link the main to industry, stores, retail, maintenance etc. It is not uncommon in Model Railroading for spurs to come directly off the main as well as off of a siding. In fact, it is common in MR to use a siding to serve an industry much as a spur would.

Switching Lead: This is an avenue to a "yard" of some type. The switching lead allows train and car movement to be carried out isolated from the main line-also known as "fowling the main". These are also refered to as A/D (arrival/departure) tracks.

Fiddle and staging tracks: These terms are usually used for the more Model RR specific meanings. These are tracks that allow you to manualy set up or stage trains to allow them to enter the layout(your main line) in an operational way. You can use these to juggle equipment, change out rolling stock and generally shuffle the deck, so to speak, to help you to simulate operations on a larger scale.

As for the sources of info- I already rambled about the value of the internet. Use it to check out another great info treasure trove-books/magazines. Go to amazon.com and search under model railroading. There will be over 400 books. Their site is very good and gives great descriptions and ratings of the books. A lot of them even have 3-10 pages posted to give you a bit of a sneak peak. Two titles I would suggest: SMALL RAILROADS YOU CAN BUILD and A REALISTIC HO LAYOUT FOR BEGINNERS. After those two, a MUST have is TRACK PLANNING FOR REALISTIC OPERATION.