Vinyl is experiencing a resurgence of popularity with the kids. :)
My husband collects vinyl, and we've got several local record shops that are generally pretty busy whenever we go in. I'd suggest checking out your city and seeing if there are any stores that you could take your collection in to see what they'd be interested in.
The big sellers are going to be the popular or influential bands/artists. I'd pull out anything like that and google to get a basic range. There are pricing guides out there like Goldmine, so you could check the library, but otherwise you'd have to check the web and ebay.
Your best return on these would be selling through ebay or the like, but that would mean you'd need to ship.
This guide is great for shipping albums:
http://www.ebay.com/gds/How-to-securely-pack-LP-record-albums-for-shipping-/10000000011707007/g.htmlThe biggest thing is to make sure the album is square in the package with no slipping around and then cushion the interior with bubblewrap or foam inserts. My husband said that a form-fitting cardboard envelope around the album, then placed inside a slightly larger package with bubblewrap or peanuts is the best method he's seen with his packages, but that might be overkill (but VERY little chance of damage that way).
If you do just take them in, check the store reviews for anyone else selling before you head over, and you might want to even call and ask them what they're interested in, and you'll probably get a decent offer if they are looking for what you've got. But we're talking a good amount of time of slogging through 100+ records, checking condition and googling for hours and then haggling - which most record stores won't do unless it is a really rare pressing... so your return on the time may not be that great unless you've got something really great.