I just got home from my first Con as someone other than the person tagging behind my son. That was so much fun. Okay, the fuzzy critter people were a bit....different, seeing the little kids in costumes was hilarious, watching the elderly mall walkers trying to figure out what the heck had invaded the mall-priceless. I also pulled the things left from our convention and did a bit of networking via chocolate and business cards. I found out several of the artists had gone to amazon and read the sample section and were interested enough to either come buy a book or point me out to someone who bought a book.
Through this I have also managed to secure a future book signing date at the card shop- not where I would have thought to have one, but, a lot of the "gamer world" reads vampires and steampunk- go figure.
One other neat marketing edge for me, I have one of those neat little things that attaches to my phone and lets me accept credit cards...that got me several sales over the ones next to me that had to point out the ATM behind us- no one wants to pay a service charge if they do not have to.
They had lots of "props" around the mall, including a tardis, which one of my granddaughters is fawning over, & that provided an idea for Christmas. My neighbor had a table display, books displayed in a doll sized coffin, which gave me the idea for something for future swag bags and got the wheels turning on what I could do future events. So other than hearing about my weekend, I hope you pick up some ideas from here or something you could alter and use for marketing your books.