I purchased a Valencia e-guide online from Berlitz, which was the most reasonable one I was able to find. I also printed out some guided walks off of a Valencia tourist site (I can't recall the name of the website at the moment).
You definitely need to visit the Central Market. Central Bar (Ricard Camarena) was really tasty unlike his flagship Michelin-starred restaurant which was a disappointment to me.
I had paella at Levante and Restaurante Navarro. Levante was a bit further from the touristy area and had more locals it seemed.
I also recommend you try horchata at the Santa Catalina horchata place. Out of all the horchata drinks I had in my three weeks in Spain recently, this one was my favorite.
For sites, check these out: Museo de Ceramica, Ciutat de les Arts i Sciences, Main Train station, and Ayutamiento (free entrance with a great balcony view over the square in front). I've left out a few places, but this should be a good start.