I have come across a selection of what I believe to be 78's. But the issue I have is a lot of them I cant seem to find information on.
I found this site as I have Halle Orchestra "The Wasps" and found it through a google search. (http://www.45worlds.com/78rpm/record/dx1088) From the comments on that page it says that the colour is different which I can confirm it is, because the one I have appears to be in very good condition.
I also have what appears to be a series of other "His Masters Voice" additions, some which are choir and others which are orchestra which I cant seem to find on.
I understand from this site it appears to be a cataloguing of 78s and others.
What I need to find out is once I've worked out what I have,what do I do next if I'm looking to sell them and how much each would be worth.
I would hunt for them on Ebay. you can search for closed listings to see what they sold for. That would give you a good idea of whether they are worth anything.
Or you can sign up for http://www.popsike.com/index.php, which compiles ebay auction prices. It's meant to focus on vinyl, but I've seen it return info for shellacs as well. A limited number of searches per day is free. The only proviso: popsike only includes records that sold for at least $22.
Unless you happened to find real rarities (blues on rare 1920s labels), most of your shellacs probably wouldn't go for more than $1-$3 in a thrift store. I've recently paid $1 for 3 records from the 1910-1920s at a rummage sale, and twice bought 90 records each (1920-1950s) for $15 from private sellers on craigslist.
collectors frenzy is better than popsike, it isn't limited and won't cut you off after a few searches to get you to sign up
but do note if you search for a record and it doesn't come up it doesn't necessarily mean you've found something mega-rare, they only list things that hasn't sold for more than a fiver!