Much of this is collectible IF its real. There has been a lot of "faux" Brilliant, Depression, and vaseline glass. Its usually easy to tell in that (EG DEPRESSION glass) will show the mold marks arent quite as crips as a known item. Id go get a book on the glass types (Schiffer Publication has a good series on collectible anything) Im sure they have a website with a catalog.
When you get a book , look at your stuff compared to the known patterns and compare. ANother way ios to visit a collection or HONEST sales barn that sells these glass types and compare one of yours.
I you can see obvious differences in the mold crispness and the glass quality itself, then your collection isnt old , its faux glass. BUT, if you have the real deal, there are price guides on the web for "prices realized recently"
Its a volatile market, with many ups and downs in value (especially now with the economy), SO if your looking to insure, thats one thing, If you want to sell, try to hang on to them with the idea that the market probably will return.
Thee glasses arent super valuable but they can be in the 60 to 100$ per item depending on the rarity of the piece and its desirability . In Depression glass, for instance, several styles of covered servers are the hottest gotta have . The early ones are mostly broken because the glass was so delicate and the pieces were so large. Id seen several of these servers go for hundreds of dollars.Same thing with AMerican Brilliant vases, they can go for up to 500$ if they are a rare and unchipped pattern.(Brilliant , since it goes back to the post Civil War, can often be ratty looking and chipped) REMEMBER CONDITION RULES over catalog prices
I dont collect any glassware , its too "yard sale" for me. But I will do some "picking" for antique dealer friends and the dealers all have APB orders out for any pieces of the rarer patterns