We've all been there; checking out books at our local library and there's a nice little book truck right there with books for sale. Or we stumble upon a great library booksale on Saturday with the kids. You may even be the hardcore bookscout, haunting every library booksale in a 100 mile radius.  Either way, you can find some good selling books at the library, even those with considerable wear and processing. Here are some tips that have always worked for me.

Check condition.  Ex-library books will have the usual processing of stamps, card pockets, mylar covers; that is to be expected. But do check for torn, loose or missing pages, notes and underlining, water stains, insect damage, etc. Libraries will also put non-library books in their sales, donated books that were never in their collection. But they may still have "discard" stamps; check the rear endpapers and inside covers. Most buyers will be more interested in the subject matter than the condition (they'll expect reading copies), but the books should still be in good solid condition.

Avoid popular fiction like the plague. Fiction and novels will probably be selling very cheaply online, especially if by popular authors.  Don't bother with these, unless you want to read it yourself. Obscure, foreign or out of print fiction may be worth buying, if you know exactly what you are buying. Do your research. However, a complete set of something (a trilogy or a series) in good readable condition can be worth a shot.

Always check the non-fiction. I always look at all the non-fiction books, the more obscure the better. If they are selling very cheaply, I'll buy a whole bunch and check them when I get home. Most of the time I find some very good listings, even for ex-library copies. Some are quite obscure or out of print, not readily available elsewhere, or else prohibitively expensive for the average scholar. Ex-library copies are a great alternative.

Look for a number of books on the same topic.  If your library has an ongoing sale or book truck of sale books, often there will be several books on the same topic. As the librarians weed out the old books section by section, they'll put them here.  If they're .75 duds sold separately, put together as a lot on Ebay they can fetch a nice price. This will work better with more specific topics: Boating, Basque History, Critical Works on a single author/genre, Sky Diving/Parachuting, Small Foods Gardening, Cartooning and Illustration, Hawaiian Stories, Horse Care, Slow Cooker cookbooks, most Crafts, etc, etc, whatever you find.  Craft books tend to do the best: Knitting, Quilting, Woodworking, Rug Making, Scrapbooking, etc. A few books on the same topic will probably sell better than just one. The buyer saves time and money, and so do you!

Short Stories. While I tend to avoid fiction, these can be great sellers, especially Horror and Science Fiction stories, stories by the same author or stories from/about a particular region or subject. I'll keep any I find and try to put them together when I have enough. Always always always include a contents list. You can often find them on other book sites, search "short story index" or the title of the book. Just copy and paste the contents list into your listing;  it's OK, it's not copyright infringement. And it will save you a ton of time, rather than typing it all yourself.

Pamphlets. I find many of these at book sales. They're usually thin paperbound items on historical or psychological subjects. They can be reports, addresses, articles, occasional papers, session notes, etc.  Either way, they are usually easy to list, store and ship. Grab them when you see them, but check their condition. For best results, store in those mylar plastic bags for protection, like a comic book.

Children's Books.  These can be worth something if sold in lots by topic. Collectors probably won't go for them, but teachers and homeschoolers will be interested in particular subjects.  Native Americans, biographies (women, African-Americans, sports heroes, etc.), specific countries/regions, folktales/myths/legends of particular regions/religions, music, sign language, holidays, disabilities and social issues are some popular subjects.

Buy in bulk.  If the books are really cheap (10 for $1.00!) or if they're having a bag sale, you can afford to be a bit less choosy. Just grab whatever looks interesting. The more you buy, the better your odds of finding good salable books.

Make lots. I find that lots of 2 to 5 books tend to sell better than any other amount. More can tend to be heavy, but that also depends on the size of the books.

Check Other Media.  Libraries may also have CDs, VHS, DVDs and other media for sale, both from the collection and donated.  They're usually worth a peek. Go for interesting and obscure items, and be sure to check condition!  I have found some interesting CDs and old VHS here, and made several nice sales.

Consider Mixed Media Lots. For Ebay sellers, consider selling books with other related items.  Got some books on a particular type of music? Maybe you can include a CD or two with the same kind of music. Books on Aaron Copland can include a CD of his music.  A Wreath book can include a package of patterns as well. Some books on African children or pastimes can include a Mancala game. Use your imagination, and you'll see all kinds of possiblities. The key here is to keep an open mind as to what can sell, and how to group things into interesting lots.

Pricing. Depending on what you pay, I think that 9.99-19.99 for about 5 books is a good reasonable price. If one particular book is worth more, than you can up it a little.  If you're not sure, price it a bit higher and include the Best Offer option.

Shipping. Media Mail works best; First Class will cost a fortune. But if your buyer asks for it, by all means offer it with the correct price.  Box up your lot and weigh it for a shipping price. Or see if they will all fit in a Flat Rate Priority Mail box from the post office. Only 8.95 or 12.95 anywhere in the country, great for a heavier lot. Be prepared for overseas shipping as well, though this can be rather high.  Have a shipping list for your lots, by weight works best for me.  1 lb - $x, 2-3 lbs - $x, etc. Weigh your books on a scale and round it up to the next pound for packing materials. Makes for much easier listing.

Leftovers. Of course, no matter what you find, there's bound to be some "oops" purchases. Not everything will be a good sale, or maybe it had damage you didn't see before. Check out my guide on getting rid of excess media items. Hope it helps.

Remember, this system is for getting rid of many books sold as lots for an OK profit, not for the big profits. You can get some nice tidy sales, but don't expect a college tuition out of this! But then again, you never know.  I sold an ex-library book purchased for .10 for $85.00.  ;-)