You could post a few of the ones you suspect might be worth something here and responders could try to advise you from their own experience and published resources. As far as I know there is no way to use the web to figure out what stuff is really worth, but only what the dreamers, scammers, and know-nothings hope to get. In the final analysis, a record is only worth what someone will pay you for it, which is why auctions are so popular.
I'd also be careful about tossing around the word "mint" if you are not an experienced record grader - most reputable sellers and guidebooks don't even use this word, feeling that it only applies to an unplayed and possibly unopened record (probably not applicable in your case) that in every detail is completely perfect as if it just came off the press. As this is really not probable with 50-60 year old records, even the best examples in existence are usually described as "near mint", and most of the cleanest ones you will find still grade out only at "excellent" (also called VG+) or "very good". This is important because the NM price is reduced by half for every drop in grade with all but the rarest and most sought-after records, and you have to know what to look for in order to comprehensively grade the record and jacket.
